SAN FRANCISCO (KGO) -- A massive fire destroyed what was left of a building in San Francisco's Mission District overnight. It was the same building that burned just 14 months ago.
The building is located on the corner of 22nd and Mission streets.
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Firefighters are still on the scene, checking for hot spots and making sure there would be no more flare ups.
It took an hour and a half to get it under control. It broke out just around midnight Monday in a vacant building.
Flames were seen shooting out of the roof.
Neighbors across the street had to be evacuated.
There was a large fire at the same building last January. Since then, it has been condemned but firefighters believe squatters were inside and may have set off some kind of heat source.
"We had a hard time getting into the building because all the doors were boarded up and the windows were boarded up from the previous fire so we had to cut our way in. The stairwell was filled with debris so we couldn't make it through the interior stairwell so we had to climb the fire escape," SFFD Div. Chief Kirk Richardson said.
Those evacuated residents have since been allowed to go home.
Firefighters are preparing to leave the scene but there's still a large investigation that has to happen to find out what the source was and how the fire started.
Part of 22nd Street is closed to traffic as you hit Mission Street.