A fire jumped Interstate 15 and stormed into Fallbrook late Monday night, weaving a path of destruction through a wide swath of the unincorporated community as it surged west and sent residents fleeing to the coast.

The outlook was bleak as officials described the fire and its potential for further destruction. By late Monday, the blaze had already burned well over 100 homes and 1,000 acres, officials said.

However, crews -- strengthened by reinforcements shortly before 10 p.m. -- were preparing to make a big stand at Gird Road to keep the flames from moving further toward the town.

Fire officials also said they were trying to keep the blaze from going south of Highway 76. If the flames were to enter the San Luis Rey River valley, authorities said they were not sure they could stop the fire from heading into Oceanside.

While the number of acres burned stood at around 1,000 Monday night, the so-called Rice fire had become the most devastating in Fallbrook's history in a little over 12 hours, in terms of the number of homes lost.

By late Monday night, roughly 120 firefighters and 25 engines fought the blaze. The fire was being held at Gird Road and Live Oak Park Road to the west, East Mission Avenue to the north and Rice Canyon Road to the east.

Rice Canyon Road was where the fire began, before crossing the freeway and setting in toward the posh Pala Mesa Resort.

Various reports said that an entire park full of mobile homes had burned down, leaving hundreds of residents homeless. Other homes near that park, dubbed "Valley Oaks," had gone down in flames, while a neighborhood of condos attached to the Pala Mesa Resort had also perished.

For hours Monday, a crew of just 13 engines and 50 personnel were doing their best to make a short-handed attempt at containing the out-of-control blaze, said North County Fire Protection District spokesman John Buchanan.

"We're not able to hold it," said Buchanan in comments around 7:30 p.m. "We're trying to hold it, and it's going right past us."

"We asked for about 20 more strike teams, and that order has not been filled yet," he said, before the additional crews arrived. "That's why we're having a problem getting in front of this thing and making a big stand."

In downtown Fallbrook, dozens of people were lined up to get gas on their way out of town around 7 p.m.

"My family left already," said 20-year-old Isabel Gaspar as she fueled her car. "My mom found a ride, so I'm the only one left here, plus my phone died, so I can't get a hold of anyone."

Still, Gaspar said she wasn't scared as she asked directions for the quickest way out of town.

"I prayed this morning that everything would be OK," she said.

The mood was somber all evening outside the downtown Fallbrook command center, where shifts of dirty, weary firefighters fueled up fire engines and ate before heading back out to the fire.

Shortly after 2 p.m., authorities ordered a mandatory evacuation through Camp Pendleton to the coast for all 40,000 people living in Fallbrook.

Less than an hour later, lines swelled on Ammunition Road, the mandated evacuation route, and outside Main Street Gas, which by that time was the only service station still selling fuel.

It was the first time a community-wide evacuation had been ordered in Fallbrook, officials said.

At 5 p.m., all roads leading out of town were still choked with traffic, as residents made their way toward coastal evacuation centers in Orange County.

Earlier on Monday, before the fire jumped over to the west side of I-15, residents who had evacuated their Stewart Canyon homes watched as the fire climbed a series of hills on its way to the interstate.

One onlooker, Fallbrook resident Andrew Pinnock, said that his mother owned a house in Stewart Canyon, although she was still moving in and did not have many possessions in the house.

"My uncle lost his house in Rancho Bernardo, so our whole family's going through a big mess," said Pinnock. "I'm afraid it might jump the freeway, and if it does, we might be in trouble."

One woman wailed as she watched a home on a ridgeline burst into flames, while another cried quietly and still others soothed the horses pinned up in trailers awaiting safe transport out of town.

As night fell, the eastern horizon glowed orange as the fire spread northwest toward De Luz and south toward Highway 76.

Contact staff reporter Tom Pfingsten at (760) 739-3516 or tpfingsten@nctimes.com.