OAKLAND (CBS SF) — A fast-moving fire roared through one of Oakland’s makeshift homeless encampments underneath the 880 freeway early Thursday, sending residents scrambling for safety.

The Oakland Fire Department said the blaze near East 12th St and 22nd Ave. was reported at about 7:34 a.m. Heavy smoke quickly drifted up on the freeway.

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California Highway Patrol officials said traffic was backed up on Highway 880 as a result of smoke from the fire.

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It took about 12 minutes to extinguish the fire, according to Battalion Chief Dino Torres.

Witnesses said one of the camp’s residents had been seen cooking earlier this morning, and Torres believes that may have been how the fire got started.

The flames raged through five tent campsites, turning them and the occupants belongings into smoldering piles of ash. All the residents were able to escape, but one dog died in the blaze.

Caltrans was sending an engineering team to the scene to make sure the charred underbelly of the overpass did not suffer any significant damage.

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