(SAN FRANCISCO) — At least one civilian and one firefighter were injured in a massive, three-alarm fire that impacted three homes in San Francisco on Thursday, according to the San Francisco Fire Department.

The civilian is in serious condition and the firefighter is in stable condition, the department said.

UPDATE 3- ALARM FIRE 3 HOMES AFFECTED- 1 INJURY AT THIS TIME- 1700 BLOCK OF 22ND AVE EVACUATED- AVOID THE AREA https://t.co/unrhslXklE pic.twitter.com/gOuwWUJ7J3

— SAN FRANCISCO FIRE DEPARTMENT MEDIA (@SFFDPIO) February 9, 2023

Over 100 firefighters descended on the scene and the fire has since been contained, the department said.

One occupant is unaccounted for, San Francisco Fire Capt. Jonathan Baxter said.

3RD ALARM WORKING #FIRE, 3RD ALARM, 1700 BLOCK OF 22ND AVE @PGE4Me @SFPD on scene @KTVU @KRON4Desk @SFFDPIO on scene pic.twitter.com/QTedtC0hpM

— San Francisco Firefighters 798 (@SFFFLocal798) February 9, 2023

Some of the block was evacuated. The fire department is urging people to avoid the area.

“We are aware of the numerous calls and reports of an explosion and houses shaking in the area,” Baxter said.

There’s no threat to the public, Baxter said.

The cause of the blaze is under investigation, the fire department said.

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