A Monroeville police car was involved in a crash with two other vehicles Monday afternoon on Business Route 22.

The crash happened at the Monroeville Mall entrance near a KFC restaurant in the 3700 block of William Penn Highway.

VIDEO: Watch Marcie Cipriani's report from Monroeville

SLIDESHOW: Photos of the crash scene on Route 22

A witness said two police cars were going through the intersection at Mall Boulevard when the second police vehicle got into a T-bone crash with a civilian car, and the impact led to a third car becoming involved in the accident.

Investigators confirm that the officer who crashed was headed to help a fellow officer with a traffic stop near the ramp to the Parkway East. Police say the driver fled from that traffic stop but was later caught and will face drug charges.

Police say the officer involved in the crash had activated his lights and sirens before driving through the intersection.

"The traffic signals automatically turn red when the police cars come through with their emergency equipment activated," Allegheny County Police Lt. Andrew Schurman said. "That triggers a response in the intersection to turn all the other intersecting roads, to turn their signals to red."

Schurman said the system was tested and appears to be working properly, but they are continuing to make sure all procedures were followed.

"I don't want to speak to Monroeville police's departmental policy," Schurman said. "I know state law mandates we make sure the intersections are clear before we proceed through them."

The officer and the two drivers were taken to the hospital. Police say one of the drivers was admitted.

Photos: Monroeville crash involving police car
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Monroeville crash

A Monroeville police officer was involved in a multivehicle crash while driving through an intersection on Business Route 22 en route to a traffic stop near the Parkway East.

Monroeville crash