A fire damaged a Martinez home Wednesday evening, but the family escaped unharmed, officials said.

Firefighters were dispatched to 501 Stevens Creek Road, at the intersection of Evans to Locks and Stevens Creek roads, at about 9:30 p.m. with fire showing at the house, said Honey Shore, spokeswoman for Martinez-Columbia Fire Rescue. They were able to bring the fire under control quickly, she added.

Smoke damage was sustained throughout the house, but fire damage was confined to a bedroom and the attic above it, Ms. Shore said.

The fire was called in by a passerby, Ms. Shore said. The homeowners were awakened by their smoke alarm, she said.

The cause is undetermined, Ms. Shore said.