California Line wildfire suspect arrested as 65,600 structures threatened

The San Bernardino County Sheriff's Department arrested a man Tuesday in connection with the Line Fire ravaging areas east of Los Angeles since Sept. 5.

Justin Wayne Halstenberg, a 34-year-old man from Norco, was identified "as the suspect who started a fire in the area of Baseline Road and Alpin Street in the city of Highland, also known as the Line Fire," the Sheriff's Department said in a press release.

Halstenberg was being held on suspicion of arson with his bail set at $80,000, officials said.

The Line Fire -- one of three large wildfires tearing through southern California -- burned 32,905 acres and was at 14% containment as of Sunday night, with around 65,600 structures threatened, according to the latest update by Cal Fire.

Authorities issued evacuation orders for 13,300 structures with another 52,300 under evacuation warnings.

No structures are confirmed damaged or destroyed. Three firefighters have been injured in the effort to contain the blaze, fire officials said.

"The Line Fire continues to grow in steep terrain with difficult access, especially in the Big Bear area," Cal Fire said. "Near-vertical slopes make putting in control lines challenging."

Stronger winds were expected through Tuesday night, "which could lead to drops in relative humidity and greater fire spread," Cal Fire said. "Towards the end of the week, cooler weather may moderate fire activity."

California authorities are grappling with two other growing wildfires -- the Bridge Fire in Angeles National Forest and the Airport Fire straddling Orange and Riverside counties.

Gov. Gavin Newsom requested Federal Emergency Management Agency aid Tuesday evening to "secure vital resources to suppress the Bridge and Airport fires."

The Bridge Fire -- burning since Sept. 8 -- was at 34,240 acres and 0% containment on Tuesday night, Cal Fire said, having seen substantial growth throughout the day. "High winds and low humidity are aiding the spread of the fire," Cal Fire's update said.

The Airport Fire -- which began on Sept. 9 -- was at 19,028 acres and 0% containment. The blaze is threatening 10,500 structures and has so far injured five firefighters and two civilians, Cal Fire said.

Newsom said in a Tuesday press release that the response effort across southern California includes "thousands of boots on the ground, including firefighters, soldiers, law enforcement and first responders, as well as air assets including 51 helicopters and nine fixed-wing aircraft."

This week, the governor called in National Guard troops and aircraft to aid the fire containment efforts.

ABC News' Marilyn Heck contributed to this report.