The federal agent, identified as Luis Alberto Olivas García, was ambushed Monday at a checkpoint in the northern state of Chihuahua, according to Mexico’s National Migration Institute.

Officials said the agent was attacked by a group of migrants at a checkpoint in the northern state of Chihuahua after asking to see their identification papers. At least two migrants were arrested.

A Mexican immigration agent was killed on Monday in Juarez, on the US border, after asking a group of migrants to identify themselves, authorities said.