Two AC Transit buses collided in San Francisco on Wednesday morning, sending four people to the hospital — including the driver of one of the buses, police said.

The collision was reported at 9:22 a.m. near Fremont and Howard streets, police spokesperson Officer Giselle Linnane.

San Francisco police spokesperson Officer Robert Rueca said one AC Transit bus was traveling north on Fremont Street when it collided with several vehicles, including another AC Transit bus. One of the buses then went onto the sidewalk and struck the scaffolding of a building, Rueca said. He said the bus did not strike anyone on the sidewalk.

Four people have been hospitalized, including the driver of an AC Transit bus that was involved in the crash, though their conditions were not immediately available.

A light pole was also struck and The City’s Department of Building Inspection has been called out to inspect it, according to fire officials.

The crash has prompted the California Highway Patrol to shut down the westbound Interstate Highway 80 off-ramp to Fremont and Folsom streets. Rueca said streets in the area were expected to be closed for several hours, and drivers should expect delays.

Bay City News Service contributed to this report.