The Riverside County (CA) Sheriff’s Department served two warrants in Orange on Thursday, one day after a man fired shots at a California Highway Patrol Officer and was then killed in a shootout with sheriff’s deputies in Lake Elsinore, officials said.

The warrants were related to the Lake Elsinore shooting, Riverside deputy Mike Vasquez told the Orange County Register.

The first warrant was served at a private residence another at a liquor store. Both the Riverside County SO SWAT team and Orange Police Department officers were involved.

The FBI’s Joint Terrorism Task Force is assisting the Riverside County Sheriff’s Department, said Laura Eimiller, an FBI spokeswoman. She she deferred questions about the investigation to Riverside because the Sheriff’s Department is the lead agency. Authorities are not saying why the JTTF was involved in the case.

The Wednesday incident began at 8:50 p.m. in Riverside County when a CHP officer pulled over a man on suspicion of driving under the influence. That incident ended with shots fired at the officer who had taken cover behind a freeway barrier.

A nearby CHP unit came to help and began chasing the suspect, who drove off and continued firing “repeatedly” as the pursuit went on, Olivas said.

The Riverside County Sheriff's Department was called to help and sent its own units and a helicopter, according to a department statement.

The chase ended when the suspect got out of his vehicle and opened fire on deputies with a rifle. The deputies returned fire and the man retreated and tried to enter a nearby home. He was killed by a responding SWAT team.