Firefighters are trying to gain an upper hand on a wildfire burning out of control just north of the City of Glendora.
The Colby Fire broke out just before 6 a.m. Thursday.
It's scorched at least 1,700 acres and has destroyed at least two homes, according to fire officials. Evacuations have taken place for 2,000 people in the area. There's at least one confirmed injury.
Flames are threatening dozens of homes in the dangerously-dry foothills of the San Gabriel mountains. At least 700 firefighters are on the ground battling the fire with the help of eight air tankers and seven helicopters.
Authorities said the battle has been made more difficult due to extremely dry conditions and the gusty Santa Ana winds.
Police have arrested three men who are believed to have started the fire: Clifford Eugene Henry Jr., 22, of Glendora; Jonathan Carl Jarrell, 23, of Irwindale; and Steven Robert Aguirre, 21, of L.A, according to fire officials at Thursday morning's press conference.
Officials said the suspects lit a campfire and windy conditions quickly caused the fire to spread.
The three men are now being held on $20,000 bail for recklessly starting a fire.
Below is an Inside Edition interview featuring a CBS cameraman who was dangerously close as the fire spread in the foothills near Glendora.