LOS ANGELES (AP) — A railroad track crossing arm crashed through a passenger window of a school bus carrying seven special-needs students and came out a window on the other side Tuesday in Los Angeles.

No one was injured in the accident southeast of downtown, which was reported at about 7:30 a.m., authorities said. Fire Department spokesman Erik Scott said the crossing arm and some broken glass ended up on one student’s lap.

Television images showed a student sitting calmly in the bus, which was stopped nearly parallel to the tracks. The crossing arm was bent and sticking through the bus.

The seven students, including three in wheelchairs, were put on another bus and taken to two elementary schools, Los Angeles County Fire Battalion Chief Dale Drummond said.

The accident occurred where a street crosses four sets of tracks operated by Union Pacific. The bus was making a left turn onto a street paralleling the tracks.

“At the intersection on the other side, there’s a stop sign,” California Highway Patrol Officer Dion Conley said. “So he stopped at the stop sign, proceeded across the tracks, and that’s when the lights started to go off.

The CHP is investigating. Conley said it will analyze whether the arm was working properly and where it was situated when the driver started making the turn.

The crossing arm was repaired, and trains were running as scheduled.

Union Pacific spokesman Justin Jacobs said the company was assisting law enforcement in the investigation.