Crews are searching for a missing boater in Fox Lake in Antioch, Illinois, on Monday night.

The Lake County Sheriff's Office said two men, whose ages were not released, were test-driving a boat when they took a turn at high speed, causing them to be ejected from the boat.

The office said neither was wearing a life vest.

One of the men was rescued by a passing boat. The other man went underwater.

As of 8:35 p.m. Monday, the office said crews were actively searching for the missing man.

No further information was immediately available.

This is a developing story. Check back for updates.