SAN FRANCISCO (CBS SF) -- Fire investigators are continuing to look into the cause of a three-alarm fire that injured 22 people and caused more than $1 million in damage at a residential hotel in San Francisco's Tenderloin neighborhood on Tuesday, Deputy Fire Chief Pat Gardner said Wednesday.

The fire was reported at 8:56 p.m. at the Franciscan Towers, a 105-unit residential hotel at 217 Eddy St.

Gardner said the blaze was apparently sparked in the trash compactor in the building's basement, and flames and smoke traveled up the garbage chute all the way to the attic, with significant fire damage around the chute on each floor.

Firefighters were eventually able to contain the fire at about 10:10 p.m.
Gardner said investigators have not yet determined the exact cause of the blaze and have found no reason to consider it suspicious.

The six-story residential hotel, which houses 113 people, is run by the Tenderloin Neighborhood Development Corporation, which also has its corporate offices and an after-school children's program in the building, said Paul Sussman, the corporation's chief financial officer.

Twenty-two people were injured in the fire, including four who required hospitalization, but none of the injuries were considered life-threatening, Gardner said.

The American Red Cross also responded to the blaze to provide blankets, food and water for the residents displaced from their homes, and worked with the TNDC to find shelter for the residents at the corporation's other buildings around the city, Sussman said.

Temporary housing has been found for all 113 residents, he said.

The residents were able to return to the building Wednesday to retrieve valuables but will not be allowed to live there until building inspectors can ensure that it is safe for them to return, Gardner said.

The top floor of the building sustained the most damage in the blaze, including a six- to 10-foot hole in the roof that partially collapsed, Gardner said.

Although the structural integrity of the building is not compromised, it has been yellow-tagged, meaning residents cannot stay there permanently until the inspectors complete their investigation, he said.

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