Mexico City (AFP) - Federal police gunned down 16 civilians in western Mexico in January, a report said, contradicting official accounts that nine people had died in the crossfire of a shootout.
The investigation by journalist Laura Castellanos, which was published Sunday by the weekly magazine Proceso and the news website Aristegui Noticias, is the latest allegation of abuse to hit Mexico's security forces.
The report came a day after the National Security Commission revealed that it had anonymously received a video that appears to show "an excessive use of force or abuse of authority by federal police officers" in Apatzingan, Michoacan state.
The commission did not provide more details and said the video was handed over to the attorney general's office to launch an investigation.
Spokesmen for the attorney general's office and the commission, which oversees the federal police, told AFP they could not comment on the report because the investigation is ongoing.
Authorities have said nine people died from "friendly fire" when former members of a rural militia clashed with federal police in Apatzingan. Officials detained 44 people that day.
But Castellanos' report, based on 39 anonymous witness accounts, videos, audio recordings and documents, said the victims were never armed with more than sticks when federal police opened fire in two incidents on January 6.
In the first event, the report said, officers shot at some 100 people who were demonstrating in front of city hall at 2:30 am, with some police shouting "kill them like dogs!"
The second shooting came hours later, when officers opened fire on a dozen vehicles carrying people who were chasing a police convoy, hoping to free their comrades, the report said.
The violence erupted as the authorities planned to disband Michoacan's "rural force," a unit comprised of vigilantes who were deputized after they rose up against the Knights Templar drug cartel.
President Enrique Pena Nieto's administration is already under fire over an alleged army massacre of gang suspects last year and the presumed slaughter of 43 students at the hands of a municipal police-backed drug cartel.