PITTSBURGH (AP) — The front of a city bus is up in the air after a sinkhole opened under it during rush hour in downtown Pittsburgh.

The Port Authority of Allegheny County says the only passenger was treated Monday morning for a minor injury.

The agency tweeted that the bus was at a red light when the street gave way and the rear half plunged into the hole.

A photo shows the front of the bus pitched into the air and the front wheels of a car that was behind it dangling over the sinkhole's edge.

Officials are waiting for a tow truck to remove the bus.