Eleven people are facing charges over a “planned ambush” that led to an officer being shot outside an Immigration and Customs Enforcement detention facility in Alvarado, Texas, last week, federal officials announced Monday.

Just before 11 p.m. on July 4, officers arrived outside the ICE Prairieland Detention Facility after a report of a suspicious person. Alvarado police noted that when one police officer engaged with the person, an unknown number of people across the street opened fire. One bullet struck an officer in the neck.