SAN FRANCISCO—San Francisco firefighters are searching for the cause of a three-alarm fire that ignited on Friday, April 7, in San Francisco’s Richmond District. According to the San Francisco Fire Department, the fire at 453 23rd Ave. was first reported around 2 a.m. The fire left four people hurt, including a firefighter, and displacing over 25 residents.

Nearly 100 firefighters from the San Francisco Fire Department assisted in dousing the Outer Richmond fire and to help residents escape.

There are three units inside the residence, and according to the fire department, there were hoarding conditions inside. Two of the victims suffered critical injuries, and a third victim suffered minor injuries. One of the victim’s suffered burns, and another suffered from smoke inhalation.

Wind and adjacent walls caused the fire spread to the two neighboring apartment buildings. A cat was also rescued from one of the buildings involved in the blaze. The SFFD contained the fire by 3:15 a.m.

Two residents were taken to the hospital for injuries sustained. The injured firefighter cut his hand while battling the blaze, and is expected to fully recover. Arson investigators are looking into the cause of the fire.