FILE - In this May 22, 2015, file photo, Mexican state police stand guard near the entrance of Rancho del Sol, where a shootout with the authorities and suspected criminals happened near Vista Hermosa,... (Associated Press) 
 
 FILE - In this May 22, 2015, file photo, Mexican state police stand guard near the entrance of Rancho del Sol, where a shootout with the authorities and suspected criminals happened near Vista Hermosa, Mexico. Mexico's National Human Rights Commission said on Thursday, Aug. 18, 2016, that it has concluded... (Associated Press) 
 
 MEXICO CITY (AP) — Federal police killed at least 22 people on a ranch last year, then moved bodies and planted guns to corroborate the official account that the deaths happened in a gunbattle, Mexico's human rights commission said Thursday. 
 
 One police officer was killed in the confrontation in the western state of Michoacan on May 22, 2015. The government has said the dead were drug cartel suspects who were hiding out on the ranch in Tanhuato, near the border with Jalisco state. 
 
 The National Human Rights Commission said there were also two cases of torture and four more deaths caused by excessive force. It said it could not establish satisfactorily the circumstances of 15 others who were shot to death. 
 
 "The investigation confirmed facts that show grave human rights violations attributable to public servants of the federal police," commission President Luis Raul Gonzalez Perez said. 
 
 Mexico's national security commissioner, Renato Sales, who oversees the federal police, denied the accusations, holding his own news conference before the rights commission had finished its own. 
 
 Sales said federal police ordered the suspects to drop their weapons and surrender, but were answered with gunfire. 
 
 "The use of weapons was necessary and proportional against the real and imminent and unlawful aggression," Sales said. "That is to say, in our minds they acted in legitimate defense." 
 
 The lopsided death toll had led to suspicions that officers might have arbitrarily killed people during the operation against suspected members of the Jalisco New Generation cartel. The rights commission questioned the government's explanation of what led to the clash in the first place. 
 
 Federal police had said they encountered a truck and took fire from its passengers before being led to the ranch. 
 
 The commission's report said the government did not produce evidence supporting that account and it said witness statements suggested 41 federal police had sneaked onto the ranch as early as 6 a.m. Officers started their assault at least an hour earlier than they maintained in reporting on the incident, the commission said. 
 
 According to the agency's report, after the federal police officer was shot, police called for backup. Fifty-four more federal police officers arrived along with a helicopter. 
 
 The helicopter fired some 4,000 rounds at the ranch house and a nearby warehouse, which caught fire. The helicopter was also hit by gunfire, the report said. One victim died of burns that the commission believes came after he was shot but still alive. 
 
 In total, five people were killed by the helicopter, the commission found. One victim was hit by a bullet that entered around his left pectoral muscle and exited his groin, but there were no bloodstains on the jeans he was found wearing, the commission said. 
 
 Thirteen of the 22 people the commission said were killed had been shot in the back, it said. 
 
 Two witnesses interviewed by the commission said federal police officers told one heavily tattooed man to run outside the ranch house and then the witnesses heard gunshots. 
 
 By the time investigators from the state Attorney General's Office arrived at the scene, "the Federal Police had approximately four hours to manipulate the scene," the report said. 
 
 Eighteen of the victims were found barefoot and one just in his underpants, leading the commission to conclude most were asleep when police arrived. The commission's investigation said 40 civilians were killed by bullets, one died in the fire and one was run over. 
 
 The government had initially refused to release autopsy reports on those killed. The commission criticized the autopsies performed by the Michoacan Attorney General's Office as being sloppy and incomplete and said the morgue turned over the wrong body to one family. 
 
 The case is reminiscent of a 2014 incident in which the commission found that soldiers killed at least a dozen suspected criminals after they surrendered in a warehouse in Tlatlaya west of Mexico City. 
 
 The army's version was that 22 suspects died in a gunfight in which only one soldier was wounded. But The Associated Press found evidence at the scene did not match that account. The warehouse wall showed signs that suspects were lined up and shot. 
 
 In that case, three women who survived were tortured by agents of the state prosecutor's office to corroborate the army's version. 
 
 On Thursday, the commission said two survivors of the bloodshed in Tanhuato had been forced to watch three slayings and were then tortured. Police threatened their lives and the lives of their families, it said. ||||| Image copyright EPA Image caption It was one of the bloodiest police operations of Mexico's drug war 
 
 The Mexican government's human rights body has accused police of killing 22 people in extrajudicial executions in a raid on a drug cartel last year. 
 
 One police officer and 42 suspects were killed in the raid on a ranch in Tanhuato, Michoacan state, on 15 May. 
 
 Officers said they had returned fire in self-defence but the high death toll aroused suspicions. 
 
 The National Human Rights Commission (CNDH) says police attempted a cover-up. Police dispute the findings. 
 
 Human rights groups in the country have long been demanding an improvement in policing standards and an end to arbitrary killings. 
 
 Previously, the government said there had been no human rights violations during the raid on the ranch. 
 
 They said a war was being fought between two local drug gangs and those killed were believed to be members of one of the cartels. 
 
 'Four thousand rounds' 
 
 Police used a Black Hawk helicopter during the operation, reportedly firing some 4,000 rounds into the ranch, known as the Rancho del Sol, during the initial assault. 
 
 The helicopter itself was hit by gunfire, investigators found. 
 
 In its report (in Spanish; warning: contains graphic images), the CNDH asserts that: 
 
 5 suspects were killed in the helicopter attack; 22 were arbitrarily executed; 15 died in unclear circumstances 
 
 2 bodies were burnt by police 
 
 2 suspects were tortured in custody 
 
 police moved bodies and weapons to cover up arbitrary killings 
 
 "The investigation confirmed facts that show grave human rights violations attributable to public servants of the federal police,'' commission President Luis Raul Gonzalez Perez said. 
 
 Mexico's national security commissioner, Renato Sales, who oversees the federal police, rejected the CNDH allegations. 
 
 "The use of weapons was necessary and proportional against the real and imminent and unlawful aggression," he told reporters. 
 
 "That is to say, in our minds they acted in legitimate defence." 
 
 Michoacan has become one of Mexico's most violent states because of the rivalry between cartels.
– Federal police executed at least 22 people on a ranch last year, then moved bodies and planted guns to corroborate the official account that the deaths happened in a gunbattle, Mexico's human rights commission says, per the AP. A total of 43 people, including one police officer, were killed in the confrontation in the western state of Michoacan on May 22, 2015. The National Human Rights Commission says five people were killed when a police Black Hawk helicopter fired 4,000 rounds at the ranch house after the officer was shot, the BBC reports. Another 22 were arbitrarily executed, while the circumstances of the other 15 deaths are still unclear, according to the commission. The lopsided death toll had led to suspicions that officers might have arbitrarily killed people during the operation against suspected members of the Jalisco New Generation cartel. Eighteen of the victims were found barefoot and one just in his underpants, leading the commission to conclude most were asleep when police arrived. Thirteen of the 22 people the commission says were executed had been shot in the back. Mexico's national security commissioner denies the accusations of what the commission called "grave human rights violations," saying federal police ordered the suspects to drop their weapons and surrender, but were answered with gunfire.