DALLAS -- Police say one person was killed and another was injured after a crash involving a motorcycle in North Dallas.

The motorcyclist and his female passenger were riding in the tunnel between Marsh and Midway at about midnight Friday when the motorcyclist stopped in the right lane, police say.

A black car didn't see the motorcycle and ran into it. The driver wasn't wearing a helmet and was killed at the scene. His female passenger was wearing a helmet but was knocked off the bike, going airborne. She was taken to the hospital in serious condition.

Police say they got a call earlier in the night about racing motorcycles, but it isn't clear if this was related.

Westbound express lanes of I-635 were closed for several hours.