Two police reports written the night that George Zimmerman shot Trayvon Martin said that Zimmerman had a bloody face and nose, according to police reports made public today. 
 
 The reports also note that two witness accounts appear to back up Zimmerman's version of what happened when they describe a man on his back with another person wearing a hoodie straddling him and throwing punches. 
 
 It has been such a contentious case that even the evidence is being disputed. 
 
 The police report states that Trayvon Martin's father told an investigator after listening to 911 tapes that captured a man's voice frantically callling for help that it was not his son calling for help. 
 
 But Tracy Martin, Trayvon's father, claims that is not true. The Martin family lawyer Ben Crump told ABC News that Tracy Martin initially listened to a distorted version of the 911 calls and said he could not identify the voice. But when he listened to a second tape that had been "cleaned," "He immediately broke down in tears because he knew it was his son calling for help," Crump said. 
 
 The new information is part of a trove of documents released by the Florida State Attorney today in the case against Zimmerman, who is charged with second degree murder for the Feb. 26 killing of Martin, an unarmed 17-year-old African American male. 
 
 Surveillance video of Martin in a store purchasing skittles right before the fatal incident was also released today. 
 
 Zimmerman, 28, is a multi-racial Hispanic man who volunteered for the neighborhood watch committee who claimed that he shot Martin in self-defense after the 6-foot tall, 160 pound teenager knocked him to the ground, banged his head against the ground and went for Zimmerman's gun. 
 
 The documents start with a criticism of Zimmerman's decision to follow the teenager, who Zimmerman said was looking suspicious. 
 
 "The encounter between George Zimmerman and Trayvon Martin was ultimately avoidable by Zimmerman, if Zimmerman had remained in his vehicle and awaited the arrival of law enforcement," an investigating officer wrote. 
 
 Zimmerman claims he got out of his vehicle to find a house number to let police know where he saw the allegedly suspicious person, and while returning to his car was knocked down by a punch in the nose and attacked by Martin. 
 
 Two police officers reported that when they arrived at the scene of the shooting, Zimmerman seemed to have a battered nose and bloodied face. One wrote that his "facial area was bloodied," and the back of his clothing was soiled with wet grass. 
 
 "Zimmerman was also bleeding from the nose and the back of his head," Officer Ricardo Ayala wrote. 
 
 Another officer wrote, "I saw that Zimmerman's face was bloodied and it appeared to me that his nose was broken." 
 
 Witnesses, whose names were redacted from the report, also lent support to Zimmerman's version of what happened. 
 
 "He witnesses a black male, wearing a dark colored 'hoodie' on top of a white or Hispanic male and throwing punches 'MMA (mixed martial arts) style,'" the police report of the witness said. "He then heard a pop. He stated that after hearing the pop, he observed the person he had previously observed on top of the other person (the male wearing the hoodie) laid out on the grass." 
 
 A second witness described a person on the ground with another straddling him and throwing punches. The man on the bottom was yelling for help, the witness told police. 
 
 The documents state that Zimmerman can be heard yelling for help 14 times on a 911 call recorded during the fight. 
 
 Yet another witness described the confrontation in emotional terms. 
 
 The witness heard "someone yelling, almost crying. Then I heard a gunshot." The witness wrote that he or she "saw a man on top of a guy laying on the ground. He was putting his hands on his neck or chest." 
 
 The man asked the witness to call 911. 
 
 "He stood up and took a couple steps away and put his hands on his head and then walked back over to the guy on the ground. He looked at him for a minute, then started to walk away toward the road. That is when the police walked up," the witness wrote. 
 
 The lead investigator on the case, Officer Christopher Serino, wrote that Zimmerman could be heard "yelling for help as he was being battered by Trayvon Martin." 
 
 Martin's death sparked public outrage after police released Zimmerman without any criminal charges for the killing. Zimmerman was later charged with second-degree murder, and the killing provoked widespread debate about racial profiling. 
 
 The autopsy also shows that Zimmerman shot Martin from a distance of between 1 inch and 18 inches away, bolstering Zimmerman's claim that he shot Martin during a close struggle. 
 
 Martin's autopsy report also revealed that there was a quarter-inch by half-inch abrasion on the left fourth finger of Martin, another indication of a possible struggle. 
 
 The teen, who lived in Miami, was in Sanford while serving a suspension for an empty marijuana bag discovered in his possession. Martin had THC, the drug found in marijuana, in his blood on the night of his death, according to the autopsy. His family told ABC News that it was "trace amounts" of THC. ||||| Story highlights Martin would be alive if Zimmerman stayed in his vehicle, police said 
 
 Trayvon Martin was pronounced dead 3 minutes after firefighters and EMS arrived 
 
 Evidence of THC, an ingredient in marijuana, was found in Martin's blood, tests show 
 
 Firefighters find forehead "abrasions" and "bleeding" from Zimmerman's nose 
 
 Just over two weeks after the fatal shooting, and less than a month before an arrest was made, police in Sanford, Florida, urged prosecutors to take George Zimmerman into custody after arguing his killing of Trayvon Martin was "ultimately avoidable." 
 
 This disclosure came out Thursday, part of a wealth of information released that is related to the case, including the medical's examiner's finding that the 17-year-old Martin had traces of drugs in his system in an autopsy conducted hours after his death. 
 
 Overall, the newly released material paints the most complete picture yet of how investigators built the case, as well as its complexity. The police perspective was most succinctly stated in a March 13 "capias request" -- a request that someone be taken into custody -- sent to the state's attorney. It speaks to the fact that Zimmerman ignored a police dispatcher's advice not to chase Martin, as well as his communications with Martin prior to the shooting. 
 
 "The encounter between George Zimmerman and Trayvon Martin was ultimately avoidable by Zimmerman, if Zimmerman had remained in his vehicle and awaited the arrival of law enforcement, or conversely if he had identified himself to Martin as a concerned citizen and initiated dialog (sic) in an effort to dispel each party's concern" the request said. "There is no indication that Trayvon Martin was involved in any criminal activity." 
 
 In his 911 call just before the shooting, Zimmerman had speculated that the teen looked like he was "up to no good or he's on drugs or something." 
 
 But Martin's defenders have portrayed Zimmerman as the aggressor, accusing him of profiling the African-American teen. Plus, one expert notes the traces of the marijuana-related substance found in the teen's system, as measured hours after his death, don't necessarily speak to any level of intoxication, while another adds that marijuana use typically doesn't make people prone to aggression. 
 
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 Martin's blood contained THC, which is the psychoactive ingredient in marijuana, according to autopsy results released Thursday. The autopsy was conducted February 27, the day after the teenager was shot dead. 
 
 Toxicology tests found elements of the drug in the teenager's chest blood -- 1.5 nanograms per milliliter of one type (THC), as well as 7.3 nanograms of another type (THC-COOH) -- according to the medical examiner's report. There also was a presumed positive test of cannabinoids in Martin's urine, according to the medical examiner's report. It was not immediately clear how significant these amounts were. 
 
 No precise levels on the urine were released. 
 
 Dr. Michael Policastro, a toxicologist, cautioned against reading too much into the blood THC levels, adding that one cannot make a direct correlation between those findings and a level of intoxication. 
 
 He also noted levels of THC, which can linger in a person's system for days, can spike after death in certain areas of the body because of redistribution. 
 
 And Dr. Drew Pinsky, an addiction specialist who hosts a show on CNN's sister network HLN, added that marijuana typically does not make users more aggressive. 
 
 Concentrations of THC routinely rise to 100 to 200 ng/ml after marijuana use, though it typically falls to below 5 ng/ml within three hours of it being smoked, according to information on the National Highway Traffic Safety Administration's website. 
 
 While some states have zero-tolerance policies for any drug traces for driving while impaired, others set certain benchmarks, the website of California's Department of Alcohol and Drug Programs notes. In Nevada, that equates to 2 ng/ml for THC and 5 ng/ml for THC-COOH, also known as marijuana metabolite. The cutoff level in Ohio is 2 ng/ml for THC and 50 ng/ml for THC-COOH. 
 
 According to the medical examiner's report, which was one of several documents on the case released Thursday by the office of special prosecutor Angela Corey, Martin died from a gunshot wound to chest fired from "intermediate range," within 36 inches. 
 
 The autopsy report lists the manner of death as a homicide. 
 
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 Zimmerman, 28, is charged with second-degree murder for killing Martin in the Sanford neighborhood where the African-American teen was staying. 
 
 Martin's father, Tracy, had taken his son with him to Sanford, about four hours away from the boy's home and where the father's fiance lived, after the teen was suspended for 10 days from Michael M. Krop High School in Miami. 
 
 According to records obtained by the Miami Herald, Martin had been suspended from school three times: once for writing graffiti on a door, another time for school truancy and the last time due to drug residue being found in his backpack. 
 
 Speaking of her son's suspension to CNN's Anderson Cooper, Sybrina Fulton said, "Whatever he had dealings with the school, it was not criminal, it was not violent, he's never been arrested." 
 
 Just before the shooting, Zimmerman called 911 to complain about a suspicious person in his neighborhood. 
 
 In the call Zimmerman, a neighborhood watch volunteer, said he was following Martin after the teen started to run, prompting the dispatcher to tell him, "We don't need you to do that." 
 
 Zimmerman apparently disregarded that advice. 
 
 Much has been made about whether Zimmerman during that call used a racial epithet in referring to Martin. But an FBI analysis, released Thursday, determined that the word could not be definitively identified "due to weak signal level and poor recording quality." 
 
 A screaming voice could be heard on other 911 calls placed by neighbors, with some speculating those screams came from Martin and others that they belonged to Zimmerman. The FBI did not make a final determination either way, citing several reasons including the fact they came during "an extreme emotional state," there weren't enough words to make a good comparison and the sound quality was low and distant. 
 
 Zimmerman claimed, according a police report released earlier, that he'd been "assaulted (by Martin) and his head was struck on the pavement." 
 
 According a report from the Sanford Fire Department , released Thursday, Zimmerman had "abrasions to his forehead," "bleeding/tenderness to his nose," and a "small laceration to the back of his head" when emergency personnel arrived at the scene at 7:27 p.m., six minutes after they were first called. 
 
 By that time, Martin had no apparent pulse, according to the fire and EMS report. Emergency personnel attempted mouth-to-mask resuscitation and chest compressions, to no avail. He was pronounced dead at 7:30 p.m. 
 
 Prosecutors have said Zimmerman, who is a white Hispanic, killed the unarmed teenager unjustly after profiling him. Zimmerman, who has pleaded not guilty, has said that he shot Martin in self-defense. 
 
 The start of the trial hasn't been set. 
 
 The case put a spotlight on race relations, spurring protests nationwide and drawing prominent civil rights leaders to central Florida denouncing the actions of Sanford police and calling for Zimmerman's arrest. Special prosecutor Angela Corey announced he'd been charged on April 11, weeks after Sanford police initially declined to do so. 
 
 It also raised questions about gun laws, as well as the merits of the "Stand Your Ground" law in Florida, and similar laws in other states that allow people to use deadly force anywhere they feel a reasonable threat of serious injury or death. ||||| The family of Trayvon Martin is asking the FBI to get involved in the investigation of the killing of the unarmed 17-year-old Florida high school student, who was shot last month by a self-appointed neighborhood watchman outside his stepmother's home. 
 
 Martin, a black high-school junior, was making his way home with a bag of Skittles and a can of iced tea on Feb. 26 when George Zimmerman spotted him, called a non-emergency dispatch number to report Martin looked intoxicated, followed him, and then minutes later after an altercation, shot him. 
 
 Zimmerman, 28, who is white, claimed self defense. He was never arrested and has been charged with no crime, sparking national outrage. 
 
 ABC News has learned police seemed to accept Zimmerman's account at face value that night and that he was not tested for drugs or alcohol on the night of the shooting, even though it is standard procedure in most homicide investigations. 
 
 Now Martin family attorney Ben Crump has written a letter to Attorney General Eric Holder, and it's being circulated by several members of congress who are putting pressure on him to get the FBI involved. 
 
 An FBI spokesman told ABC News: "We are aware of the incident, we have been in contact with local authorities and are monitoring the matter." 
 
 The night of Feb. 26, Zimmerman made a non-emergency call to police before fatally shooting Martin, in which he told a dispatcher, "This guy looks like he's up to no good, on drugs or something." 
 
 But law enforcement expert Rod Wheeler who listened to the tapes tells ABC News that Zimmerman, not Martin, sounded intoxicated in the police recordings of the 911 calls. 
 
 "When I listened to the 911 tape the first thing that came to my mind is this guy sounds intoxicated. Notice how he's slurring his words. We as trained law enforcement officers, we know how to listen for that right away and I think that's going to be an important element of this entire investigation," Wheeler said. 
 
 But Zimmerman was not tested. 
 
 Martin's family is now calling on the FBI to take over what they say is a botched investigation. 
 
 "We've got a fair investigation, it was the best we can do, it's in states attorney hands now," Sanford Police Department spokesman Dave Morgenstern said. 
 
 Series of Calls to Police Record Events Leading Up to Shooting 
 
 The series of calls to police, which depict the apparent progression of events that led to Zimmerman allegedly shooting Martin, sent the boy's mother screaming from the room and prompted his father to declare, "He killed my son," according to a family representative. 
 
 The contents of the calls and the family's reaction to them were recounted to ABC News by a representative of the boy's family, Ryan Julison, and ABC News affiliate WFTV published excerpts from the 911 calls. 
 
 On one call to a non-emergency dispatch number, according to Julison, Zimmerman says, "He's checking me out," and then, "This guy looks like he's on drugs, he's definitely messed up." 
 
 "These a**holes always get away," he adds. 
 
 The dispatcher is heard trying to discourage Zimmerman, asking, "Are you following him?.. Okay, we don't need you to do that." 
 
 Within minutes, however, 911 calls are being made to police reporting the two are fighting. 
 
 "They're wrestling right in the back of my porch," one frantic caller says. "The guy's yelling help and I'm not going out." 
 
 On a second call someone's screams for help can be heard and what sounds like two gunshots. 
 
 The caller's boyfriend shouts, "Get down," and after the second apparent gunshot, the shouts for help cease, Julison told ABC News. 
 
 "There's gun shots. Uh, I'm pretty sure the guy is dead out here, holy sh**," a caller says into the phone. 
 
 One witness describes Zimmerman after the shooting. 
 
 "He's out there with a flashlight. The guy is raising his hands up saying he shot the person," the caller said. 
 
 Martin's family listened to eight tapes, Julison said. At one point, Sybrina Fulton, Trayvon's mother, ran out of the room screaming and crying, barely lasting through half the tapes. 
 
 The boy's father, Tracey Martin, stoic and measured until then, erupted, Julison said. 
 
 "He killed my son," Martin said, according to Julison. "He killed my son. He couldn't control himself." 
 
 The Sanford, Fla., Police Department, relenting to massive public pressure, plans to release parts of the 911 tapes pertaining to the shooting, multiple sources told ABC News, but wanted the boy's family to hear the tapes before they were released to the public, according to a family source. 
 
 A week after ABC News uncovered questionable police conduct in the investigation of the fatal shooting, including the alleged "correction" of at least one eyewitness' account, outrage that the shooter remains free is intensifying. 
 
 "It's surprising. It's shocking," said Tracy Martin, Trayvon's father. "It lets me know that justice is just not being served here. All we want is justice for our son. We're not asking for anything out of the ordinary." 
 
 In an interview with ABC News, Martin's mother, Fulton, tearfully said she only seeks an arrest. 
 
 "Let a judge and jury decide the rest," she added. 
 
 In the meantime, outrage is spreading across the Internet. 
 
 The Seminole County State Attorney's Office was so bombarded by emails demanding that it prosecute Zimmerman that its website had to be taken down for 45 minutes, according to a spokeswoman for the office. 
 
 One of several petitions for Zimmerman's arrest has garnered more than 250,000 signatures on a change.org site, and at one point signatures were pouring in at the rate of 10,000 an hour, according to the website. 
 
 The outrage has been partly buoyed by calls for non-violent action by hip-hop luminaries, including Russell Simmons, who has been tweeting about the tragedy and warning against its possible vigilante violence. 
 
 "Trayvon Martin didn't die so we can create a race war he died so we can promote better understanding. We must start honest dialogue," Simmons wrote. 
 
 It may have been an allusion to a statement by a group called the New Black Liberation Militia, which planned to travel to Sanford, Fla., next week to enact a citizen's arrest against Zimmerman and bring him to federal authorities. 
 
 Sanford, Fla., Police Chief Billy Lee said Zimmerman asserts he shot Martin out of self-defense. 
 
 "Until we can establish probable cause to dispute that, we don't have the grounds to arrest him," Lee said last Tuesday. 
 
 Martin had been staying at his father's girlfriend's house and stepped out. On his way back into the gated suburban Orlando community, Martin was spotted by Zimmerman. 
 
 Zimmerman described Martin as suspicious because he was wearing a hooded sweatshirt and walking slowly in the rain, police later told residents at a town hall. 
 
 A dispatcher told him to wait for a police cruiser, and not leave his vehicle. 
 
 But about a minute later, Zimmerman left his car wearing a red sweatshirt and pursued Martin on foot between two rows of townhouses, about 70 yards from where the teen was going. 
 
 Zimmerman's pursuit of Martin did not of itself constitute a crime, Lee said. 
 
 Witnesses told ABC News a fistfight broke out and, at one point, Zimmerman, who outweighed Martin by more than 100 pounds, was on the ground and that Martin was on top. 
 
 Austin Brown, 13, was walking his dog during the time of the altercation and saw both men on the ground but separated. 
 
 Brown, along with several other residents, heard someone cry for help, just before hearing a gunshot. Police arrived 60 seconds later and the teen was quickly pronounced dead. 
 
 According to the police report, Zimmerman, who was armed with a handgun, was found bleeding from the nose and the back of the head, standing over Martin, who was unresponsive after being shot. 
 
 An officer at the scene overheard Zimmerman saying, "I was yelling for someone to help me but no one would help me," the report said. 
 
 Witnesses told ABC News they heard Zimmerman pronounce, "It was self-defense," and place the gun on the ground. 
 
 But after the shooting, a source inside the police department told ABC News that a narcotics detective and not a homicide detective first approached Zimmerman. The detective peppered Zimmerman with questions, the source said, rather than allow Zimmerman to tell his story. Questions can lead a witness, the source said. 
 
 Another officer corrected a witness after she told him that she heard the teen cry for help. The officer told the witness, a long-time teacher, that it was Zimmerman who cried for help, the witness told ABC News. 
 
 Lee publically admitted that officers accepted Zimmerman's word at the scene that he had no police record. 
 
 Two days after the incident, during a meeting with the victim's father, Tracy Martin, an officer told the father that Zimmerman's record was "squeaky clean." 
 
 Yet public records showed that Zimmerman was charged with battery against on officer and resisting arrest in 2005, a charge that was later expunged. 
 
 In a letter to the Orlando Sentinel, Zimmerman's father contended his son is not a racist. 
 
 "At no time did George follow or confront Mr. Martin. When the true details of the event became public, and I hope that will be soon," the letter said, "everyone should be outraged by the treatment of George Zimmerman in the media." 
 
 "I asked [the police], 'Well, did you check out my son's record?'" Tracy Martin told ABC News in an interview Sunday. "What about his? ... Trayvon was innocent." 
 
 Trayvon Martin's Family Seeks Justice 
 
 Trayvon Martin had no arrest record or disciplinary action for violence as a student in North Miami's Krop High School. 
 
 On Monday, Lee, seeking to head off racial unrest, tried to reassure the public that his department was doing all it could to reach a fair conclusion, as some in the crowd heckled him by saying, "a little black boy is dead." 
 
 Lee's department said it plans on passing its investigation over to the state's attorney office to determine whether to press charges against Zimmerman. 
 
 Trayvon Martin's parents described him as the kind of son who, even at 17, allowed his parents to kiss him publicly. 
 
 "That was my baby, my youngest son," his mother, Sybrina Fulton, told ABC News in an interview in Miami. "He meant a lot to me, I don't think the police department really understands that. ... I need justice for my family, I just want justice for my son." 
 
 Fulton is incensed that Zimmerman left his car despite being urged by dispatchers to stay put. 
 
 "My son didn't do anything," she said. "He was walking home from the store. Why would the neighborhood watch guy would have a weapon? ... It's just crazy. You are supposed to watch the neighborhood, not take the law into your own hands." 
 
 ABC News' Matthew Rosenbaum contributed to this report.
– Get ready for a deluge of information in the Trayvon Martin/George Zimmerman case, as prosecutors today released a cache of related documents. Some early samples: Pro-Zimmerman: His lawyers surely hope lots of attention will be paid to the fact that Trayvon apparently smoked pot at some point before the altercation. (It's not clear when or how much.) The autopsy found traces of the drug THC in his system, the active ingredient in marijuana, reports CNN. Also, ABC News notes that two witness accounts given to police "appear to back up Zimmerman's version" of events. Pro-Trayvon: Prosecutors will no doubt point to the police conclusion that the shooting was "ultimately avoidable," had Zimmerman "remained in his vehicle and awaited the arrival of law enforcement." The Orlando Sentinel leads its story with it. Zimmerman photo: The documents include a grainy copy of a photo police took of Zimmerman after the shooting in which he appears to have a bloody nose, notes AP. See the photo here. Trayvon's belongings: He had $40.15 on him, along with a packet of Skittles, a red lighter, headphones, and a photo pin in his pocket. See for yourself: MSNBC has the documents here in PDF form, and the Sentinel has crime-scene photos here. Click to read about a damning assessment of the Sanford police by the New York Times here.