A federal law enforcement source told CBS News that local police arrested eight people. The official said some of those apprehended were wearing body armor.

A Blue Alert was issued on Wednesday for a man accused of shooting an Alvarado police officer during an attack at a U.S. Immigration and Customs Enforcement detention facility on July 4, according to the Texas Department of Public Safety and the FBI.

Officials believe the suspects intended to draw ICE detention officers out of the building by launching fireworks at the facility.