An elderly woman was seriously injured when a school bus and two SUVs collided in Montgomery County.

The accident happened shortly before 9 a.m. Tuesday at Buchert and Kepler roads in Lower Pottsgrove Township.

The driver of an SUV stopped at the stop sign on Kepler Road before pulling into the path of the school bus traveling east on Buchert Road, police said. The bus hit the passenger side of the SUV, causing both vehicles to hit another SUV that was stopped on the opposite side of the intersection.

A passenger in the first SUV, Lilian Yerger, 85, of Pottstown, was trapped in the wreckage with serious injuries, police said. She was rushed to the trauma center at Reading Hospital.

The driver, Marvin Yerger, also 85, was not injured. He will be cited for a stop sign violation, police said.

The driver of the SUV was treated at the scene for general complaints of pain but did not have to go to a hospital, police said.

The school bus driver was not injured. He had just dropped off students at the nearby Pottsgrove Elementary School before the crash, police said.