The residents of an east Petaluma home were displaced after a fire sparked in the home’s garage early Saturday, a fire official said.

Fire crews responded to a structure fire reported just before 1 a.m. Saturday in the 2100 block of Willow Drive in Petaluma, according to a news release from the Petaluma Fire Department.

Firefighters arrived on scene within three minutes of the report, officials said, and saw smoke coming out of the garage of the residence.

Upon arrival, the responding battalion chief requested additional resources from Rancho Adobe Fire District, Gold Ridge Fire District and the Sonoma Valley Fire District.

Crews knocked down the fire within 20 minutes, officials said, but remained at the house for several hours to extinguish it fully and put out hotspots.

No injuries were reported during the blaze and the occupants of the home, who were not identified, were not present at the time of the fire, authorities said.

The Petaluma Building Department and Pacific Gas & Electric Co. assessed the home after the fire to evaluate structural safety and red tagged the residence as unsafe.

The Petaluma Fire Department said the cause of the fire is still under investigation.