FILE - Children light candles in memory of those killed in clashes with federal forces in the central square of Apatzingan, Michoacan, Mexico, Jan. 7, 2015.
FILE - Children light candles in memory of those killed in clashes with federal forces in the central square of Apatzingan, Michoacan, Mexico, Jan. 7, 2015.

MEXICO CITY - Prosecutors in Mexico said Thursday they have arrested six federal police officers in connection with a series of shootings in 2015 in which at least eight demonstrators died.

They are the first arrests under the current administration of federal police, a force that President Andres Manuel Lopez Obrador has downsized and criticized as corrupt and inefficient.

A federal official who was not authorized to be quoted by name said the officers were arrested on homicide and attempted homicide charges related to the 2015 shootings in the western state of Michoacan.

The federal Human Rights Commission has said at least six of the demonstrators were victims of use of excessive force or execution and another may have been run over by a police vehicle.

FILE - A military patrol drives past family members and funeral home workers waiting to pick up the bodies of people killed a day earlier in Apatzingan, outside the forensic morgue in Morelia, Michoacan, Mexico, Jan. 7, 2015.

The killings occurred as federal police broke up a protest in which demonstrators allegedly linked to a drug gang had taken over the city hall in the Michoacan town of Apatzingan. 
 
Police at the time said the protesters were armed and opened fire, at one point even suggesting the demonstrators might have been hit by friendly fire from their own side. In the end, police gave several differing versions of the events.

Demonstrators claimed police had altered the scene and planted guns next to the victims' bodies.

The clash did include other incidents in which protesters attacked police.

The confrontation occurred when Michoacan was in the final stages of a vigilante uprising to kick the Knights Templar cartel out of Michoacan. The Viagras gang sought to take over much of the area around Apatzingan after the other cartel was defeated.