The blaze erupted around 5:50 a.m. Thursday in the Angeles National Forest near Glendora Mountain Road and Colby Way. The blaze was 30 percent contained as of 11 p.m.
Flames spread rapidly and moved down the hill toward homes, forcing 3,700 people to evacuate.
Glendora residents were allowed back in their homes at 6 p.m. Azusa residents, however, remained under an evacuation order due to a fire flare-up that was coming down the mountain in Azusa toward Highway 39, north of Sierra Madre Avenue. Officials said 870 homes in the Azusa area were still evacuated as of 11 p.m.
The Colby Fire destroyed five homes and damaged 17 buildings. One of the homes destroyed by flames was a guest house on the campus of the historic Singer Mansion, a 1920s Spanish estate built by heirs to the Singer sewing machine fortune on Kregmont Drive.
"We're just thankful that no one is hurt," said Jeania Parayno, who lives on the property. "We got out just in time. The wind was so strong that the fire just engulfed the whole place."
Parayno said 10 tenants were displaced by the fire. Two of the main buildings on the property are still standing, which Parayno calls a "miracle."
Resident Steve Whittenberg of Glendora said he also saw a structure catch fire.
"We saw embers start underneath the eaves ... and it was fully involved," Whittenberg said.
The city of Glendora has declared a state of emergency to try to get federal funds to help evacuated residents.
More than 550 firefighters surrounded homes for structure protection, said L.A. County Fire Inspector Keith Mora. Three helicopters and two Super Scoopers were also key to the fire fight.
Glendora police arrested three men and booked them for recklessly starting a fire.
Smoke from the Glendora fire was seen from miles away, and communities throughout Los Angeles County, including Palos Verdes, Torrance and Cerritos, saw ash falling from the sky. The South Coast Air Quality Management District has issued a smoke advisory for parts of Los Angeles County, urging people to avoid unnecessary outdoor activities.
Three injuries were reported from the fire. Authorities say a civilian and a firefighter suffered minor burn injuries, and a another firefighter suffered a minor ankle injury.
The fire comes as the Southland faced another day of dry and windy conditions. A red-flag warning was supposed to expire Wednesday night, but the National Weather Service extended it until 3 p.m. Friday due to persistent winds and low humidity levels.
The red-flag warning applies to the San Gabriel and Santa Monica mountains, the Santa Clarita, San Fernando and San Gabriel valleys, the Los Angeles coastal zone, the Westside, metropolitan L.A., Orange County and Ventura County.
People who need overnight shelter can go to the American Red Cross shelter located at Glendora High School at 1600 E. Foothill Blvd. in Glendora. Evacuation centers that were set up at Memorial Park in Azusa and the Duarte Community Center have been closed.
Evacuated pets can be brought to the Pasadena Humane Society, 361 S. Raymond Ave; the Inland Valley Humane Society, 859 E. Sierra Madre Ave., or Memorial Park in Azusa, 320 N. Orange Place. A shelter for evacuated horses has been set up at the Pomona Fairplex, Gate 12, 1101 W. McKinley Ave.
Officials said evacuated animals that were taken to the Los Angeles County Animal Care and Control's evacuation trailers are being transported to the Baldwin Park Care Center located at 4275 N. Elton St. in Baldwin Park.
SCHOOL AND ROAD CLOSURES
All streets north of Sierra Madre Avenue from Glendora Mountain Road to Yucca Ridge were closed. Highway 39 and Glendora Mountain Road are shut down, and traffic was slow on the 210 Freeway because the Glendora fire was visible to drivers. Azusa Police closed Garcia Trail.
The Glendora Unified School District closed several schools, including La Fetra, Cullen, Goddard, Sandburg and Sellers. Citrus College and St. Lucy's Priory High School were also closed for the day.
All schools in the Azusa Unified School District are scheduled to be in session Friday, but outdoor activities were to be limited, according to Azusa Police.