Firefighters from Murrieta were among those continuing to battle a 1,700-acre wildfire in the Angeles National Forest Friday morning.
An engine crew from the Murrieta Fire Department was sent to the fire lines Thursday night to provide mutual aid, according to Murrieta fire Chief Matt Shobert.
Firefighters took swift action as the Colby Fire flared up overnight. Crews maintained scorched are to approximately 1,709 acres, north of Glendora and Azusa. The blaze was about 30 percent contained as of Friday morning.
Cal Fire/Riverside County also sent strike teams to aid more than 1,100 personnel on the blaze that has destroyed five homes and damaged 17 other structures, causing minor injuries to three people.
Nine helicopters and two SuperScooper aircraft were also deployed.
Overnight, firefighters worked to put out hot spots near structures, an
effort that was expected to continue throughout the day.
One of the homes that was lost was a guest house on the nearly 6-acre
campus of the Singer Mansion, a 1920s estate built on Kregmont Drive by heirs
to the Singer sewing machine fortune.
A trio of young men is accused of starting the fire when they tossed papers into a campfire. They were located by local law enforcement and taken into custody.
Fueled by gusting winds and fed by exceedingly dry vegetation, the fire exploded across hundreds of acres. Late Thursday afternoon, firefighters had halted the fire's forward progress, officials said.
One resident -- a woman who suffered a minor burn while trying to fight the fire -- was injured but not taken to a hospital, according to fire officials.
Two firefighters were also injured. One of them suffered an ankle injury that did not require hospitalization, while the other was taken to a hospital for treatment of a minor burn, authorities said.
On Thursday, about 3,500 people were evacuated from an area north of
Sierra Madre Avenue between State Route 39 in Azusa to Glendora Mountain Road
in Glendora. About 6 p.m. Thursday, the evacuation order was lifted in
Glendora, but it remained in effect Friday in Azusa.
There is still fire burning on the backside of the hill closest to the city, immediately above the evacuated area, authorities said, describing it as an active fire that firefighters are working hard to control.
Meanwhile, strong winds, low humidity and warm temperatures threatened to fuel wildfires throughout most of Riverside County for the fifth consecutive day Friday.
"High pressure aloft along the west coast will keep very dry and warm conditions across Southern California through this weekend, with daytime humidity values in the single digits," according to the National Weather Service.
There was a brief lull in the winds Thursday afternoon but speeds increased again Thursday evening and early today, prompting the NWS to extend a red flag warning for the Inland Empire and mountain areas until 6 p.m. today.
The warning, first issued Monday, was originally set to expire Wednesday and then later extended to 6 p.m. Thursday. It signals a heightened risk of wildfire and is the agency's most serious fire-related weather warning.
This week's red flag warning did not extend to the Coachella Valley.
Today's forecast for the Inland Empire and mountain areas called for sustained northeast winds of 15 to 30 miles per hour and gusts up to 50 mph. Isolated gusts up to 60 mph were also possible, an NWS advisory said.
The low daytime humidity was expected to be around 5 percent.
—City News Service and Maggie Avants contributed to this report.