All-hands-on-deck ordered as 3 LA-area wildfires have burned more than 100,000 acres

Three rapidly growing Southern California wildfires have burned more than 100,000 acres in less than a week and continued to threaten homes in multiple communities as the state mobilized an all-hands-on-deck response to bolster front-line fire crews battling the raging flames.

Nearly 6,000 National Guard members, law enforcement officers and other first responders have been sent to the firelines. Additionally, a squadron of 51 firefighting helicopters, nine fixed-wing aircraft, including two National Guard C-130 airplanes, 520 fire engines, 75 bulldozers and 141 water tankers were being used in an attempt to tame the blazes, two of which were out of control Wednesday.

The biggest blaze is the Bridge Fire, which ignited Sunday in the Angeles National Forest about 31 miles east of downtown Los Angeles and exploded overnight from about 4,000 acres on Tuesday to nearly 48,000 acres by Wednesday morning, according to the California Department of Forestry and Fire Protection.

The fire remained out of control with 0% containment after spreading across Los Angeles and San Bernardino counties, destroying the Mountain High Ski Resort where images emerged of the chairlift going up in flames. The fire is also threatening the small mountain communities of Wrightwood and Mt. Baldy, officials said.

At least 33 homes in Wrightwood and Mt. Baldy have been destroyed and another 2,500 structures in the area are being threatened by the fire, according to Cal Fire.

The cause of the fire remains under investigation.

During a news conference Wednesday, Los Angeles County Sheriff Robert Luna said three people, including an off-duty sheriff sergeant, were trapped by the Bridge Fire about 5 miles west of Mt. Baldy in Los Angeles County. Luna said efforts are underway to rescue the people, who are unable to access roads and need to be airlifted out of the remote area. Luna said heavy smoke in the area was preventing a helicopter from reaching the trapped people and the Los Angeles County Fire Department was attempting to get to them by vehicle.

"It's just a nightmare," Candace Lace, a homeowner in Lake Elsinore, a town being threatened by the Bridge Fire, told ABC News. "My girlfriend lost her home and I had to call her and tell her she's losing her home. I could see it on fire."

By Wednesday morning, the Bridge Fire had consumed 47,904 acres and prompted numerous evacuation orders and warnings, according to Cal Fire.

Stephanie Beck, a resident of Wrightwood, told ABC News that she has never seen a blaze move as quickly as the Bridge Fire.

"We really didn't even have time to think," Beck said of evacuating the fire zone. "It was just throw everything in the car and go."

The Line Fire

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, California, 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 statement.

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

As of Wednesday, the Line Fire had burned 34,659 and was at 14% contained, according to Cal Fire. The sprawling fire is threatening more than 65,600 structures, including homes and commercial property, according to the latest update.

Authorities issued evacuation orders for 13,300 structures with another 52,300 under evacuation warnings. Evacuation orders were issued for 9,200 structures in the area, with another 56,400 structures under evacuation warnings, Cal Fire said.

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

"Today elevated winds and continued dry conditions will allow the fire to grow," Cal Fire said in a statement. "Smoke from fires across the region will help moderate fire activity unless the skies clear and the smoke thins. That would allow for more slope and vegetation aligned runs.

More than 3,100 firefighting personnel were battling the blaze.

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

The Airport

The Airport Fire -- which broke out on Monday in an unincorporated area of Orange County and spread to Riverside County -- had burned 22,376 acres as of Wednesday, growing by 3,348 acres overnight, according to Cal Fire. The blaze is 0% contained.

The blaze is threatening 10,500 structures, including homes and businesses, and has so far injured five firefighters and two civilians, Cal Fire said.

The Airport Fire began around 1 p.m. PT on Tuesday, sparked by county public works crews working on a fire prevention project by trying to move boulders to prevent public access -- mostly by motorcyclists -- to an area of the canyon with a lot of dry vegetation that could ignite easily, officials told ABC Los Angeles station KABC.

At a news conference Tuesday afternoon, officials said 1,400 homes in Robinson Ranch in Rancho Santa Margarita were under mandatory evacuation due to the fire moving south toward communities like Lake Elsinore and Dove Canyon.

A total of 16 active wildfires were scorching California on Wednesday and have burned 613,819 acres, according to a statement Gov. Newsom released Tuesday.

So far this fire season, 6,045 wildfires have erupted in California and consumed more than 900,000 acres, Newsom said.

ABC News' Marilyn Heck contributed to this report.