A fierce, wind-whipped brush fire has spread along the coast of the US state of California, threatening several thousand homes and a military base as local authorities ordered an evacuation.
Some 4,000 homes were threatened, with evacuations ordered for about a quarter of those residences on Friday, according to the the fire department in Ventura County, just northwest of Los Angeles.
Fears arose after gusty Santa Ana winds from the northeast faded and ocean breezes from the southwest pushed inland.
The "worst-case weather scenario" sent flames ripping through fresh fuel just to the east of where the blaze charred wildlands a day earlier, said Ventura County fire spokesman Bill Nash.
"In the perfect scenario we'd just hope for the wind to go away, but what happened is the wind just turned around,'' Nash said.
As of daybreak on Friday, authorities had contained about 10 percent of the perimeter of the blaze, which has scorched some 4,047 hectares of dry, dense brush. Several farm buildings and recreational vehicles were engulfed, and fire officials said 15 homes were damaged, along with five commercial properties.
Another 25 outbuildings were destroyed, but no residential structures were lost and no injuries have been reported, according to Ventury County officials.
In all more than 3,000 firefighters were battling six major wildfires across the state, the state fire agency said.
Fire managers said they expected it would take until next Monday to contain the spread of the wildfire.
The so-called Springs Fire and a flurry of smaller blazes around the state this week marked an abrupt start to a California fire season that weather forecasters predict will be worsened by a summer of high temperatures and drought throughout much of the western US.
"We're seeing fires burning like we usually see in late summer, at the height of the fire season, and it's only May," said Tom Kruschke, also of Ventura County fire department.
In the town of Camarillo, temperature hit a record high of 35.5 degrees Celcius by late morning on Friday, according to the National Weather Service.
The blaze, possibly ignited by a tossed cigarette butt, broke out at early Thursday morning local time north of the Pacific coast, and quickly spread to the fringes of the communities of Camarillo and Newbury Park.
By Friday morning, flames had advanced to within a short distance of the ocean's edge in some places, forcing authorities to close several miles of Pacific Coast Highway.
At the Point Mugu US Naval Air Station on the coast, a base housing unit that is home to 110 active-duty military personnel and their families was evacuated because of heavy smoke.
California State University at Channel Islands campus, including student housing, was closed for a second day, the university said in a website posting, though official evacuation orders for the school were lifted.
The fire reinforced predictions that California is in for a bad summer fire season because dry winter and spring weather has left brush tinder-dry.