PHILADELPHIA (CBS) – Police are investigating an early morning accident that involved a Pennsylvania State Trooper.

The accident happened early Thursday morning on the Schuylkill Expressway near the ramp for City Avenue.

According to investigators, a vehicle somehow struck the state trooper’s cruiser. It was not immediately confirmed, but it was believed that the driver fled the scene on foot after the accident.

The condition of the trooper was not immediately known. The trooper’s cruiser had to be towed from the scene.

The accident remains under police investigation.