SAN FRANCISCO (CBS SF) — Four people were injured when a San Francisco Fire Department ambulance transporting a patient was broadsided by another vehicle Friday evening in San Francisco’s Excelsior neighborhood.

The collision happened around 5:20 p.m. near Alemany Boulevard and Congdon Street, according to fire spokesman Jonathan Baxter.

The ambulance had its lights and sirens on and was transporting a patient to the hospital. A silver sedan failed to yield at the intersection and struck the ambulance on its side, police said.

Three of the victims suffered injuries that were not considered life threatening, according to Baxter.

Some of the victims were paramedics inside the ambulance, although it wasn’t clear how many, Baxter said.

Two of the victims were taken to the hospital.

One of the victims hospitalized was the patient that was initially being transported to the hospital. That victim suffered life-threatening injuries, according to Baxter.

“The collision did not stop any life-saving measures and the patient was transported immediately to the hospital,” Baxter said.

The driver of the silver sedan that struck the ambulance stayed at the scene and cooperated with the investigation, according to Baxter.

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