WALNUT CREEK (CBS SF) — A two-alarm fire at a Walnut Creek retirement community on Tuesday night left at least four people displaced from their homes and two apartments badly damaged, Contra Costa County Fire Protection District officials said Wednesday.

The fire was reported around 10:30 p.m. at a building within the Rossmoor retirement community in the 2600 block of Saklan Indian Drive, Fire Marshal Robert Marshall said.

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Fire crews arrived on the scene to find that the residents had safely evacuated the building, which had smoke coming from its roof.

Firefighters found a fire burning in a large attic space within the building and were able to get the blaze under control in about 20 minutes, Marshall said.

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No injuries were reported.

The fire marshal said at least four people were displaced by the fire, which caused an estimated $250,000 in damage to the building and its contents.

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Fire investigators haven’t determined what caused the blaze but suspect it may be linked to the building’s electrical system, Marshall said.