GUERNEVILLE (CBS SF) — Four people were hospitalized and power lines knocked down after a two-alarm fire broke out early Monday morning at a Russian River resort, a Sonoma County Fire dispatcher said.

Firefighters were called around 3:45 a.m. to reports of a blaze at the Guerneville Lodge at 15905 River Road, according to the dispatcher.

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When crews arrived, multiple occupants were still inside the building. Four occupants were transported to an area hospital, and the American Red Cross was called to assist others at the scene. The extent of the injuries was not immediately known.

No firefighters were reported injured in the blaze, which was knocked down around 4:30 a.m., according to the dispatcher.

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The cause of the fire is under investigation, and crews remained on the scene as of 6:30 a.m.

The blaze also sent two power lines across both lanes of traffic on River Road, which has been closed from Bonita Avenue to state Highway 116, according to the CHP.

A fire dispatcher said that PG&E crews have been called to the scene to repair the power lines.

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