Investigators probing the death of "Top Gun" director Tony Scott said they still don't know why he plunged from the Vincent Thomas Bridge on Sunday. 
 
 Law enforcement sources said several notes Scott left do not mention any health problems or offer solid clues about why he jumped. It's possible, the sources said, that authorities might never make a clear determination of motive. 
 
 An autopsy was performed Monday. But, as in many cases, the coroner said a final cause of death would not be determined until toxicology and other test results became available in several weeks. 
 
 Officials have not determined whether Scott had any health problems before he jumped off the San Pedro bridge but said family members have denied media reports that he was suffering from cancer. 
 
 "The family told us it is incorrect that he has inoperable brain cancer," said Craig Harvey, a chief with the coroner's office. 
 
 Several people who were driving over the bridge when Scott jumped described witnessing what happened. 
 
 "He was on the roadway close to the fence looking around. He was looking around and fumbling with something at his feet. He looked nervous," David Silva told The Times. 
 
 Silva said he was a passenger in a car on the north side of the bridge and Scott was on the south side. 
 
 Silva said Scott "paused a couple of seconds and then began to climb the fence. He put his foot on the top of the fence and paused again. And then he threw himself off. I immediately thought, that guy is dead." 
 
 At first, Silva and other motorists thought the jump was an extreme-sports stunt. Then they realized the jumper didn't have a parachute or safety cord. 
 
 Silva said he called 911 immediately. 
 
 A Rancho Palos Verdes man who was driving across the bridge said the director appeared "determined" and "resolute." 
 
 Eric Brill, 59, said he was returning home after visiting his mother in Laguna Woods when he spotted a man wearing multicolored clothing climbing one of the cables on the other side of the bridge. The man was "clambering up in a very strong way," Brill said, something that confused him until he read later that Scott was an avid rock climber. 
 
 "It takes a while to register in your brain, because you're not used to seeing anything like this and for a few seconds you think it's some kind of mistake," Brill said. "I looked more closely — perhaps it's a maintenance man. But I knew very soon after that it wasn't anyone doing maintenance." 
 
 As Brill was about to drive past Scott, he said, the director "turned around, as if to see if someone was after him." 
 
 "I could very, very clearly see his face," Brill said. "He was very determined. He was not crying, he didn't look upset, he didn't look sad. He just looked very resolute." 
 
 Brill said he had read accounts from witnesses describing him as nervous and fidgety. 
 
 "I didn't see that," Brill said. "What I saw was a very determined guy." 
 
 richard.winton@latimes.com 
 
 kate.mather@latimes.com ||||| Silva said he was a passenger in a car on the north side of the bridge and Scott was on the south side. 
 
 "He was on the roadway close to the fence looking around. He was looking around and fumbling with something at his feet. He looked nervous," witness David Silva said in an interview with The Times. "I thought it was some extreme-sports guy." 
 
 Scott appeared nervous before leaping off the bridge Sunday afternoon, a witness said. 
 
 Scott, 68, had just completed a new movie, and there had been no public reports of health problems. 
 
 "The family told us it is incorrect that he has inoperable brain cancer," Harvey said. 
 
 But Craig Harvey, a chief for the coroner's office, said Scott's family denied media reports about brain cancer. 
 
 The autopsy will look at any major health issues Scott had. 
 
 The "Top Gun" director jumped off the Vincent Thomas Bridge on Sunday in what is being investigated as a suicide. As in many cases, the coroner said it would not have a final cause of death until toxicology and other tests are back in several weeks. 
 
 The Los Angeles County coroner's office said it has not determined whether director Tony Scott had any health problems before he jumped off a San Pedro bridge Sunday and said family members have denied media reports that he was suffering from inoperable brain cancer. 
 
 Silva said Scott "paused a couple of seconds and then began to climb the fence. He put his foot on the top of the fence and paused again. And then he threw himself off. I immediately thought, that guy is dead." 
 
 At first, Silva and other motorists thought it was an extreme-sports stunt. Then they realized the jumper didn't have a parachute or safety cord. 
 
 Silva said he called 911 immediately. 
 
 The coroner's office said all evidence suggests that Scott took his own life. 
 
 Scott left a suicide note at his office, law enforcement sources said, but police have not revealed what it said. Harvey said Scott also left several "instructional" notes to family and friends. 
 
 Simon Halls, a spokesman for Scott's family, said the family asked "that their privacy be respected at this time." 
 
 Los Angeles police first learned of the incident after 12:30 p.m. from a 911 caller who said a man had leaped off the suspension bridge that connects San Pedro and Terminal Island. It's a 185-foot fall from the bridge roadway to the waters of the Los Angeles Harbor. 
 
 Authorities have been talking to those on the bridge at the time of the incident. 
 
 A source said officials looked inside the car and determined that it belonged to the famed action-movie director and producer. A note in the car had contact information for his wife. The suicide note was later found in his office, according to law enforcement sources. 
 
 His body was pulled out of the water several hours later by divers from the Los Angeles Port Police. 
 
 The coroner's office identified Scott on Sunday evening. 
 
 Scott was a respected director and producer whose films included "Man on Fire," "Enemy of the State" and "Beverly Hills Cop II." 
 
 The last film he directed was "Unstoppable," a 2010 thriller about a runaway freight train. 
 
 His career in television included executive producing the series "The Good Wife" and "Numb3rs," both on CBS. 
 
 The British director, who lived in Beverly Hills, was best known for the 1986 hit "Top Gun," starring Tom Cruise as a Navy aviator. The movie grossed $21.6 million in its first 11 days of release. 
 
 Scott was one of three sons born to working-class parents in northern England. 
 
 He established his career as a commercial director and continued to make television spots late into his career. Before becoming a filmmaker, Scott was a painter. 
 
 Known for a kinetic visual style that aimed to take audiences into his high-octane action scenes, Scott also produced a number of blockbuster movies, most recently "Prometheus," directed by his brother Ridley Scott, and "The A-Team." 
 
 At the time of his death, he had recently completed filming "Out of the Furnace," a drama he was producing about an ex-con, starring Christian Bale. The movie is set to come out next year. 
 
 Scott was also preparing to produce a science fiction drama called "Ion" and had served as executive producer on "Stoker," set to come out in March. 
 
 His debut feature, 1983's vampire movie "The Hunger," starred Catherine Deneuve and established Scott's cinematic style. He followed that movie with "Top Gun," which not only boosted the career of Tom Cruise but also ushered in a series of Scott's action movies, which included "Days of Thunder," also starring Cruise, and "Crimson Tide," starring Denzel Washington. 
 
 Though his movies were consistent box-office hits, Scott rarely attracted critical praise and was never nominated for an Academy Award. 
 
 He was more successful with reviewers in television, however, for his work on "The Good Wife." 
 
 Scott was married three times and had twin sons with his third wife, actress and model Donna Wilson. 
 
 ALSO: 
 
 Director 'looked nervous' before jumping off bridge 
 
 Tony Scott's death treated as suicide; autopsy planned 
 
 Witnesses saw 'Top Gun' director Tony Scott jump off bridge, police say 
 
 -- Richard Winton and Andrew Blankstein
– The reason that drove Tony Scott to leap to his death from an LA bridge may never be known. Law enforcement sources tell the LA Times that the director left a few notes, but none of them give any motive for the suicide, including health problems. A witness who was driving across the bridge when Scott jumped says the director, a rock climber, was "clambering up [the bridge cables] in a very strong way. … He was very determined. He was not crying, he didn't look upset, he didn't look sad. He just looked very resolute." Scott had filmed parts of Unstoppable underneath the very same bridge, and in 2009 the director said he wanted to shoot part of a Warriors remake there, according to the Hollywood Reporter. The Reporter also has previously unpublished quotes from an interview it did with Scott in May, in which he called himself "a bull" and said that work was his "drug of choice." A friend of Scott's told NBC News that the director struggled with depression "throughout his life," E! reports.