Traffic along Reisterstown Road came to a halt yesterday morning after a Baltimore County police car flipped onto its roof, creating a barricade at Slade Avenue in Pikesville.

Cpl. Vicki Warehime, spokeswoman for the county Police Department, said Officer Michael L. Bortner was responding to a nearby accident when his car collided with another about 10 a.m.

Bortner had a red traffic signal but had his "full lights and siren" on when his car collided with a 1995 maroon Toyota Camry driven by Shirley Cohen, 82, of the 3600 block of Clarks Lane in Northwest Baltimore, Warehime said.

The spokeswoman said witnesses told investigators that Cohen's car, which was northbound on Reisterstown Road, slammed into the driver's side of the police car, sending it airborne.

The police car rolled onto its rooftop sirens, ripping the roof off the car, shattering the windows and throwing the back seat cushion onto the pavement.

After colliding with Bortner's car, Warehime said, Cohen's car struck a traffic-signal box and the curb before hitting a NationsBank branch.

The officer was flown by MedEvac helicopter to Maryland Shock Trauma Center, where he was treated and released.

Cohen was treated at Sinai Hospital and released yesterday afternoon.

Pub Date: 4/21/99