California Highway Patrol Officer Chris Bol may be pretty accustomed to the way his radar setup works while he’s on the hunt for speeders, but it had him befuddled a few days ago when the gear in his vehicle started “going crazy” without a car in sight.

The patrolman eventually decided to get out of his Ford Explorer and have a look around the deserted stretch of territory, intent on finding what his radar gun was getting a return from — and then it suddenly became very, very apparent.

It turns out the speeder Officer Bol’s radar gun kept alerting him to wasn’t on the road at all, but was flying low overhead and coming around on another pass: an F-16 Fighting Falcon.