At least 37 armed civilians and two federal police officers were killed in a clash Friday in western Mexico, a region torn by drug cartel violence, a federal government official told AFP.
The shootout took place in the morning in the municipality of Tanhuato, in the state of Michoacan, and the death toll was a "preliminary figure," the official said on condition of anonymity.
The official did not provide more details.
Tanhuato is near Yurecuaro, a town where a former vigilante leader who was running for mayor was shot dead during a campaign event last week.
Farmers formed vigilante forces in Michoacan in 2013 to drive out the Knights Templar drug cartel, which has been weakened by arrests of its top leaders.
Tanhuato is also near the border with Jalisco state, where the powerful Jalisco New Generation drug cartel has battled security forces in deadly clashes this year.