MEXICO CITY, April 19 (Reuters) - Three media outlets said on Sunday that Mexican federal police killed 16 unarmed people in two separate attacks in January, appearing to contradict an account by the federal government that the deaths could have been caused by friendly fire.
Aristegui Noticias, Univision and Proceso published similar accounts of the deaths in Apatzingan in the restive western state of Michoacan. They were the latest reports to allege abuses by security forces in the country.
There was an international outcry over the September disappearance of 43 students who the government said were abducted by local police in league with a drug gang. The case has dragged down President Enrique Pena Nieto's approval ratings.
The reports on Sunday detailed the deaths of 16 people during attacks by police on Jan. 6 in Apatzingan.
The federal police had no comment on the reports.
The National Security Commission, which oversees the federal police, said on Saturday that it had received an anonymous video "from which one can infer the alleged excessive use of force or abuse of power by federal policemen in Apatzingan."
A spokesman for the interior ministry said authorities always investigate allegations of police abuse when there is sufficient evidence, but did not say if an investigation was under way in this case.
The media reports said those killed in Apatzingan, mostly members of vigilante groups created to counter the region's powerful gangs, had been protesting their lack of pay from the federal government, which had co-opted them into a new rural police force last year.
Citing testimony from dozens of survivors and families of victims, the reports said police fired on the protesters, who were not armed.
Images accompanying the reports showed bloody bodies around a white truck. Witnesses quoted in the reports said several victims received no medical attention and bled to death on the street.
The news stories appeared to be at odds with the explanation given by Alfredo Castillo, then the federal government's security commissioner for Michoacan, who said on Jan. 12 the deaths could have been caused by gunfire from the vigilantes themselves.
Castillo stepped down from his post in January under pressure over his failure to contain violence in the state.
Pena Nieto has faced heavy criticism over abuses by security forces since 22 suspected gang members died in an army confrontation last June in Tlatlaya, in the central state of Mexico. Authorities have charged three soldiers with murder and four with dereliction of duty in that case. (Reporting by Anahi Rama; Writing by Alexandra Alper; Editing by Frances Kerry)