PLEASANTON (CBS SF) – Three people were sent to the hospital and a home was heavily damaged resulting from a fire that broke out in Pleasanton early Thursday morning.

According to firefighters, the Livermore-Pleasanton Fire Department and the Alameda County Fire Department responded to a home on Driftwood Way around 6:50 a.m., saying they found “heavy fire” at the residence.

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Firefighters said they were able to evacuate three residents from the home. The residents were treated at the scene for minor to moderate injuries before being transported to the hospital.

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Firefighters on the scene of a fire on Driftwood Way in Pleasanton, February 4, 2021. (Livermore-Pleasanton Fire Department)

Firefighters on the scene of a fire on Driftwood Way in Pleasanton, February 4, 2021. (Livermore-Pleasanton Fire Department)

About an hour later, the fire was brought under control, firefighters said. No firefighters were injured.

Damage is initially estimated at $850,000.

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Firefighters said the cause has not been determined. A joint investigation with firefighters, the Pleasanton Police Department and the Alameda Arson Task Force is underway.