Twenty-three Panther Valley Middle School students were sent home this morning after their Kistler Transportation school bus was suddenly stopped while in Summit Hill.

Panther Valley School District Superintendent Dennis Kergick said the incident happened at about 8 a.m."The Summit Hill bus for some reason came to an abrupt stop, and some of the kids were banged around as a result. Some of the students complained about possible injuries," he said.School district nurses examined each student. Seventeen of the students said they had bumped their heads or faces on seats. One on a window, another had abrasions on an elbow, four said they had been jolted forward and backward. One girl had a bruise on cheek, Kergick said.In all, 23 students were sent home and their parents were called."We're conducting an investigation," Kergick said. "We contacted Summit Hill police, and they are also conducting an investigation."Kergick said the district has taken statements from the students. He declined to release information about the bus driver.The school district is under contract with Kistler Transportation for bus service.Kergick said the company's drivers are required to pass background checks because they are in contact with children. He also said there may have been a video camera operating on the bus. The buses switch out active and dummy cameras, and he was not sure which was on the bus involved.Summit Hill police Chief Joseph Fittos did not immediately return a telephone call this afternoon.