BELLEVILLE, Ill. (WAND) - A St. Louis County police officer and one other person are dead after a crash on Thursday night. 

The three vehicle crash happened on Route 159 and Brick School Rd. around 11 p.m. That is about 20 miles south of Belleville. 

Illinois State Police said another driver was trying to pass a truck on two-lane Highway 159 when the off-duty officer's vehicle was struck head-on. The officer was killed, and a passenger in the car that struck the officer's vehicle also died.

The driver of the passing vehicle survived with serious injuries.

The officer and other person who died in the crash have not been identified.