A fire in a residence at 67 Billou St. in south San Rafael displaced four people Wednesday afternoon, San Rafael Fire Department Battalion Chief Jim Lydon said.

The fire in the garage was spreading to the attic and interior of the residence when firefighters arrived at 1:25 p.m., Lydon said.

All the occupants were out of the single-story, single-family residence, Lydon said.

Twenty-seven firefighters limited the damage to the garage area, but the blaze caused some smoke and heat damage to the living space in the home, Lydon said. 

Fire crews checked within ceilings and walls to make sure the fire had not spread, Lydon said.

Firefighters from Kentfield, Ross Valley, Mill Valley, Marinwood and Novato assisted San Rafael firefighters, Lydon said.

No injuries to the residents or firefighters were reported and crews remained on the scene late this afternoon to check for hot spots.

The cause of the fire was undetermined Wednesday, Lydon said.