A wildfire spreading north-west of Los Angeles has forced hundreds of people to leave their homes.
The fire front approaching Los Angeles is 16km (10 miles) long
The blaze, which has already destroyed 6,800 hectares (17,000 acres) of land is said to be 5% contained so far.
Some 3,000 firefighters have managed to save hundreds of buildings, with only one officer reported injured.
The fire, which started on Wednesday, developed very quickly, but winds are calming down and the authorities say they are "guardedly optimistic".
Eleven helicopters are pouring water and fire retardant on the flames to contain their advance, but firefighters say steep terrain and strong winds are hampering operations.
State of emergency
So far, only one house has been destroyed and four more buildings have suffered some damage.
Suburbs evacuated include Chatsworth, Oak Park and Lake Manor.
But more people might have to leave their homes if the blaze continues to spread.
"If the weather continues to cooperate and the public continues to cooperate, this may end well for all of us, but the weather is unpredictable in these parts," Los Angeles county supervisor Zev Yaroslavsky told AFP news agency.
High temperatures and thick, dry undergrowth allowed a small fire which started in the San Fernando Valley some 50km (30 miles) northwest of Los Angeles to get out of control and threaten the city in less than 24 hours.
The causes of the blaze are unknown. An investigation has already been launched.
Los Angeles authorities have announced they will declare a state of emergency to unblock emergency funds.
Many of the evacuees have found shelter at Red Cross shelters, while others are staying with friends.
The largest wildfires on record in California destroyed more than 300,000 hectares (750,000 acres) of land in 2003, leading to the evacuation of 100,000 people.