CONCORD (KRON/BCN) — Firefighters scrambled to put out a brush fire that broke out behind an apartment building in Concord Monday morning. Flames charred roughly a half-acre of vegetation, according to a fire marshal with the Contra Costa County Fire Protection District.

Firefighters arrived on the scene at 11:16 a.m. to a report of a fire in a creek bed behind the Clayton Creek Apartments, located at 5255 Clayton Road, Fire Marshal Robert Marshall said.

Flames briefly threatened the building, Marshall said, but crews were able to contain the blaze quickly and had it extinguished about 10 minutes after arriving on scene.

There were no reports of injuries.

The cause of the fire is under investigation, but Marshall said investigators suspect discarded smoking materials might have sparked it.

Fire officials urge the public to be extra careful to prevent the start of fires, saying heat and wind conditions right now are optimal for fires to spread.