SAN FRANCISCO (CBS SF) — A residential fire has grown to three alarms in San Francisco’s Ingleside neighborhood Monday morning, a fire department spokeswoman said.

The blaze was reported at 8:56 a.m. at a house in the 1100 block of Plymouth Avenue, San Francisco fire spokeswoman Mindy Talmadge said.

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Talmadge said firefighters arrived to heavy smoke at the scene at the rear of the building and that two buildings are involved.

In addition, she said two patients are being treated.  One was a passerby who tripped and fell. The other is a firefighter being treated for exhaustion.

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Talmadge initially said firefighters were looking for two people reported possibly in a lower rear unit in the building.

She could not give an estimate for when the fire will be contained although the smoke was dissipating very rapidly.

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