GRIFFITH PARK (CBSLA.com) — Fire crews on Saturday afternoon said a brush fire that burned three to five acres in Griffith Park had been knocked down.

The fire started near the 4900 block of Griffith Park Drive shortly before 3 p.m. Saturday, the Los Angeles County Fire Department said.  It had burned 2 acres by 3:00 p.m.

By 3:30 p.m., more than 100 firefighters were on the scene and making good progress, LAFD said.

Shortly after 4 p.m., firefighters said the fire was knocked down in 1 hour and 37 minutes and had burned 3-5 acres.

No structures were threatened. The cause of the fire was under investigation.

This is a developing story. Check back for updates.