TUCSON, Ariz. — Police in Tucson say they’re investigating a fatal motorcycle crash on the city’s southwest side.

They say the name of the man killed is being withheld until his family can be notified.

Police say the motorcycle collided with a pickup truck around 7 p.m. Saturday.

A police officer who was leaving the Pima County Jail came across the collision moments after it happened.

The officer saw the motorcycle driver lying unresponsive in the roadway and began administering CPR until paramedics arrived, but the man was pronounced dead at the scene.

Police say the motorcyclist was wearing a helmet at the time of the collision.

They say the driver of the truck remained at the crash scene and no signs of impairment were detected.