Imprisoned landless farmer leader Ruben Villalba, who is on his 17th day of a hunger strike, wears a sign on his head that reads in Spanish "Freedom or death" as he attends his pre-trial hearing at court in Col. Oviedo city, Paraguay, Thursday, Feb. 14, 2013. Behind is fellow farmer Nestor Castro, who is also on a hunger strike. The prosecutor says he has no physical evidence showing who killed six police officers during a bloody land dispute that prompted the downfall of Paraguayan President Fernando Lugo. He says he didn't even try to determine who killed 11 farm workers who also died when the bullets started flying. Villalba and Castro are on hunger strike to protest their eight month imprisonment without formal charges. Prosecutor Jalil Rachid attends a pre-trial hearing for landless farm workers in Col. Oviedo city, Paraguay, Thursday, Feb. 14, 2013. Even so, Rachid has said he'll ask a judge on Thursday to formally charge 10 peasants who survived the fusillade with attempted homicide, and punish them with up to 25 years in prison. Imprisoned landless farmers Felix Balmori, center, and Adalberto Castro, right, enter the court room handcuffed to each other for their pre-trial hearing in Col. Oviedo city, Paraguay, Thursday, Feb. 14, 2013. Even so, Jalil Rachid has said he'll ask a judge on Thursday to formally charge 10 peasants who survived the fusillade with attempted homicide, and punish them with up to 25 years in prison. Judge Jose Benitez attends the pre-trial hearing of landless farm workers in Col. Oviedo city, Paraguay, Thursday, Feb. 14, 2013. Even so, Jalil Rachid has said he'll ask Judge Jose Benitez on Thursday to formally charge 10 peasants who survived the fusillade with attempted homicide, and punish them with up to 25 years in prison. CURUGUATY, Paraguay (AP) - The prosecutor says he has no physical evidence showing who killed six police officers during a land dispute that prompted the downfall of Paraguayan President Fernando Lugo. He says he didn't even try to determine who killed 11 farmworkers who also died when the bullets started flying. Even so, Jalil Rachid concluded that 10 peasants who survived the fusillade should be charged with attempted homicide, and punished by up to 25 years in prison. He's also seeking lesser charges against four other people. "It's obvious that the farmworkers ambushed the police," said Rachid, who spent six months investigating the clash. In the official version he presented to Judge Jose Benitez, Rachid said that farmworkers fired first after police came to conduct a census of the families occupying land controlled by a powerful Paraguayan politician, and that police officers fired back in self-defense. The arrested farmworkers deny firing any weapons, and insist that the police provoked the clash. Paraguay's lack of institutional controls and the chaos of last June's deadly standoff have made it difficult to get at the truth. But peasants and their supporters say that the prosecutor led a one-sided investigation, and that both he and Judge Jose Benitez have blatant conflicts of interest. On Thursday, Benitez indefinitely delayed his preliminary hearing after they accused him of "malfeasance" for hearing the case despite having ruled in 2009 that the politician, Colorado Party Sen. Blas Riquelme, could annex the land in question. That ruling was later appealed. "Benitez lacks the moral standing to evaluate the prosecutor's evidence against my clients because years earlier he favored Riquelme, giving him the state land now in litigation," defense attorney Vicente Morales told The Associated Press on Thursday. Morales says Rachid is biased because his father was close friends with Riquelme - accusations Rachid dismissed as political threats meant to influence April's presidential election. The shootout last June gave the Colorados and other Lugo opponents the political ammunition needed to quickly vote the sandal-wearing leftist out of office. They accused him of "mismanaging" the occupation and giving peasants false hopes for land reform. The most detailed version yet of how the shootout may have started was described by one of the 40 fugitives from the clash, who fled into the forested hills of northern Paraguay. Speaking on condition of anonymity out of fear for his life, he told the AP that he was standing just a few meters from the first men to fall. Tensions were already boiling over on the 5,000-acre (2,000 hectare) ranch known as Marina Cue in Curuguaty, a district some 200 miles (320 kilometers) northeast of the capital, where Paraguay's forests have been bulldozed into vast fields of soy in mechanized operations that employ relatively few people but bring vast profits to landowners. The dispute went back decades, with peasants alleging that the land was stolen from the state by Riquelme, whose party supported dictator Alfredo Stroessner from 1954-1989. The former senator died of a stroke in September at age 82 without receiving title to the property. Landless families had tried for years to persuade authorities to redistribute the land as part of Paraguay's long-promised agrarian reform. Finally, several dozen families decided to occupy a small corner of the property. Hundreds of heavily armed officers from around the country responded, armed with a warrant from Judge Benitez to take a census of the occupiers. The fugitive said gunfire erupted after Police Officer Erven Lovera, who was trained by the FBI to handle tense negotiations, spent five minutes speaking with Avelino Espinola, who represented the peasants. The discussion between the two was very heated. Espinola told the police chief not to cross a line, a wire fence, that divided the police and the farmworkers," said the fugitive. He said Lovera "sprayed pepper spray at our comrade Francisco Ayala, who had raised a machete he was carrying," said the fugitive, speaking softly under the trees in Paraguay's native Guarani language. When Ayala fell to the ground from the pepper spray's effects, Espinola pounded Lovera's chest with both hands in anger, and was immediately shot and killed, followed moments later by Lovera, the fugitive said. Waves of gunfire then ripped through the tall grass. The prosecution insists the clash began with the farmworkers opening fire on the police. But the fugitive's account, if true, raises another possibility - that both negotiators, surrounded by hundreds of officers, were killed by police gunfire after Espinola pushed Lovera. Without ballistics tests showing who fired the bullets that killed both men, it's a possibility that Rachid's investigation hasn't ruled out. Morales said he had not previously heard anything about Ayala raising a machete or Lovera using pepper spray, because his clients were 100 or more meters (yards) away from the negotiators when the gunfire erupted and unable to see what happened. The fugitive said he escaped by crawling through the grass. "I haven't turned myself in to the prosecutor because I'm afraid the police will kill me," he said. Two identified gunmen in December killed Vidal Vega, a surviving leader of the peasant movement who was to testify in the case. After the shootout last June, police quickly abandoned the crime scene and hundreds of people arrived, looking for bodies. Some collected hundreds of spent bullet casings, but Rachid refused to accept them because there was no way to prove where they came from. Rachid didn't include any ballistics tests in his report that might support the farmworkers' version of events. Instead, he focused on the officers: His report says five of the officers died of pellets from 12 and 28-gauge shotguns, and the sixth - not Lovera - was shot by a .38 caliber revolver. No such evidence was gathered from the farmworkers' bodies. Rachid's report says they were shot by officers "defending themselves using their standard police weapons," without describing what weapons or bullets were involved. Most police in Paraguay don't carry standard-issue weapons, however: their departments are so underfunded that officers buy their own handguns and bullets. The farmworkers' death certificates attribute the cause to unspecified "gun injuries." Martina Paredes said she found the body of her brother Luis the next day, "with a gunshot to the head, from above to below." "For us it was a summary execution, but the prosecutor didn't open any investigation," she said. Rachid said last year that he didn't know who shot whom. More than 330 officers from various departments participated in the clash. Of those, 84 officers gave sworn testimony to Rachid but none identified any gunman, or were able to say what weapons the defendants allegedly carried. While the future of the criminal case remains unclear, about 150 people have been gathered near the ranch since Sunday, threatening to invade again if the government doesn't agree by Friday to carve out parcels for them. "We are outside the farm and ready to once again occupy the state's land," said Leonor Vega, president of Landless Commission of Curuguaty.