NORTH BEND, Ore. -- A driver suffering from a medical complication lost control of her car on a two-lane bridge across Coos Bay, sparking a three-car crash that shut down Highway 101 for two hours Wednesday.

Investigators believe Jackie Bernard, 54, of Reedsport, Ore., lost control of her 2003 PT Cruiser as she drove north across the McCullough Bridge over Coos Bay due to an unknown medical complication.

The PT Cruiser hit the curb, then drove into the southbound lanes and collided with the rear of a 2006 Chevrolet bus driven by Danielle Otten, 30, of Eugene, Ore.

The crash caused the bus to slide sideways, first onto the southbound sidewalk, then into the northbound traffic lane where the bus collided with a 2005 Honda Civic driven by Jill Knight, 30, of Coos Bay, Ore.

Both Bernard and a passenger in the bus, Aieriel Davidson, 20, of Medford, Ore., were injured and taken to the hospital.

The McCullough Bridge was closed to traffic for about two hours while the scene could be cleared up by Mast Brothers Towing, South Coast Towing, and the Oregon Department of Transportation.  A detour was set up for southbound traffic over East Bay Drive. Northbound traffic was closed.

Early reports indicated four cars were involved in the crash. Police later said three cars were involved.