San Francisco firefighters battle 4-alarm blaze in city's North Beach neighborhood

SAN FRANCISCO (KGO) -- A massive 4-alarm fire broke out in San Francisco's North Beach neighborhood Saturday night.

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The fire broke out at 659 Union Street around 7:30 p.m. and quickly escalated to four alarms.

VIDEO: Massive fire erupts at building in San Francisco's North Beach

A massive fire erupted at a building in San Francisco's North Beach on St. Patrick's Day. Here's a look at some of the most powerful imagery.

Smoke and flames could be seen from across San Francisco Bay.

Firefighters said 15 people were displaced and there were no injuries reported.

The Red Cross was assisting the displaced residents.