Mexico City ? A shootout between police and suspected cartel hit men in central Mexico Friday left at least 12 people dead and one police officer wounded, officials said.

Guanajuato state Attorney General Carlos Zamarripa said police and soldiers were checking a report of armed men at a building in the town of Apaseo el Alto when assailants opened fire and lobbed grenades at them.

All the 12 dead were gunmen, Zamarripa said. Twelve suspects were detained.

Gov. Juan Manuel Oliva said one police officer was wounded in the shootout in Guanajuato.

The group was allegedly working for the Zetas, a gang of assassins tied to the Gulf cartel.

Mexico is suffering a wave of gang violence that has killed more than 10,800 people since President Felipe Calderon took office in December 2006 and launched a military-led crackdown on drug traffickers.