At least six gunmen died in separate shootouts with federal law enforcement agents and army troops in Piedras Negras, a border city in the northern Mexican state of Coahuila, officials said.

The first shootout occurred around 10:30 a.m. on Monday and involved federal law enforcement agents and gunmen, with four suspected criminals ending up dead, Coahuila Attorney General’s Office spokesmen told Efe.

Two federal law enforcement agents wounded in the shootout were taken to a hospital in the border city.