It took Mohammed and Umme Islam almost a dozen years of saving money, but the couple from Bangladesh was finally able this year to redo the Falls Church apartment they share with their three children.

Yesterday morning, they watched it burn.

The Islams were among the families huddled yesterday afternoon outside the three-story Timberlane Village Garden Condominiums, looking on as firefighters walked through the roofless, ash-covered building where a four-alarm fire had begun sometime before 3:30 a.m. The fire left one resident hospitalized with critical burns and many others homeless.

"We have nothing," Umme Islam, 34, said as she sat on the grass in the courtyard of Timberlane, a complex of apartment buildings. "We have nothing."

The fire occurred at 7316 and 7318 Lee Highway, two attached structures where about 100 people rent or own mostly two-bedroom apartments, like the Islams'.

"The place was shaking. My husband just said, 'Grab the children and get out of here,' " Umme Islam said. She and her husband, who works at a Taco Bell, had just spent $20,000 in savings to remodel the unit they owned. They have no insurance.

About 30 people were in the building when the fire erupted, setting off what residents described as "explosions" and large cracks in the walls that made people think there had been an earthquake.

The fire started accidentally in a natural gas-powered furnace in a third-floor apartment, said Lt. Raul Castillo, spokesman for Fairfax County's Fire and Rescue Department.

The unidentified man who lived in that apartment jumped off his balcony, apparently to get away from the fire, Castillo said. The victim was airlifted to Washington Hospital Center with critical burns, he said.

"I'm so glad we heard the boom or we would have been killed," resident Rajesh Thanju said.

Neighbors called Thanju a hero for dialing 911 and then running up and down the hall banging on doors and standing outside in the courtyard, yelling for people to get out. Thanju wore bandages on his shins, covering spots where he was hit by glass from blown-out windows. "There was a hole in the wall into the next apartment, and flames were shooting through," he said.

Police said the number of residents at home was lower than usual because of the holiday weekend. Many residents are new immigrants who said they had expected to work all weekend but now would be busy trying to find a place to live.

Mauricio Gutierrez, 27, had been renting his apartment with three other men for only a week. He was supposed to be at his job as a cook yesterday but instead waited his turn to be escorted into the building to retrieve what was left of his possessions.

"I don't know yet where I'll go," he said.

While some people gathered in the shady courtyard, breaking out coolers and food for their now-homeless neighbors, dozens more were at a nearby school, where Red Cross and Fairfax County officials distributed housing information. Residents said they were provided with three nights' hotel accommodations and then were to contact the county for further shelter.

Some residents said the fire department arrived quickly after the fire began yet waited to start extinguishing it. "They could have saved the second part of the building," Umme Islam said.

"They put all the ladders up and all the hoses and then they were waiting," Thanju said.

Castillo said there was no delay.

The first resident to be escorted into her apartment emerged with a small plastic bag and began sobbing.

"Nothing, nothing," repeated the woman, who declined to give her name as she was surrounded by people trying to comfort her.

"How did it look inside?" asked one boy.

The distraught woman simply shook her head.

Joe Campbell carries items salvaged from his apartment at Timberlane Village Garden Condominiums in Falls Church.Fairfax County firefighter Sarah Goldman waits as Rajesh Thanju gathers what he can from his third-floor apartment. Officials said the fire began in a natural gas-powered furnace in an apartment on Thanju's floor.