A brush fire burned more than 200 acres north of Azusa in the Angeles National Forest as extreme heat overtook the region, forcing evacuations.
The Los Angeles County Fire Department reported the blaze was burning at 9501 San Gabriel Rd. near Morris Dam at about 2 p.m. The fire had burned 217 acres and was 40-percent contained Friday morning.
The fire, dubbed the Dam Fire, was running uphill in heavy brush.
Mandatory evacuations were ordered north of Morris Dam to Crystal Lake, including cabins and campgrounds. An evacuation route was organized out through East Fork to Glendora Mountain Road.
Highway 39 was closed due to the fire, which was growing quickly. It was expected to remain closed through Sunday.
No homes were at risk.
Tankers with Phos-Chek as well as helicopters were making drops, holding the line on the blaze. The aerial attack continued into the night.
The blaze grew from about 25 acres to 240 acres in less than two hours, according to the Glendora Police Department and the U. S. Forest Service.
The fire is in steep terrain, some of which is near vertical, fire officials said.
A heat advisory and an excessive heat warning started at 11 a.m. and will last through Saturday evening, NBC4's Belen De Leon said. Hot and dry weather is expected across SoCal through the weekend.