PORTER -- A Porter volunteer firefighter died Sunday when flames trapped him and three other firefighters inside a burning building in Montgomery County.

The fire that killed Gary Staley, 33, who had been with the department about a year, broke out about 9:45 a.m. at a classic and antique car showroom at Loop 494 and Hammond north of Kingwood.

Porter firefighter Juan Chapa, 20, and Allen Haynes, 28, of the New Caney Volunteer Fire Department escaped but were rushed to Memorial Hermann Hospital with second- and third-degree burns to the face, neck and chest.

"It's my understanding that they are stable at this time," said senior investigator Jimmy Williams of the Montgomery County Fire Marshal's Office.

The fourth firefighter made it to safety and was treated by paramedics at the scene.

State and county fire marshals and the arson task force from the federal Bureau of Alcohol, Tobacco and Firearms were at the scene late Sunday, searching through the building's remains.

Officials said they didn't know what sparked the flash fire.

Firefighters, wiping away tears and holding each other for support, formed an honor guard as the flag-draped body was carried to a hearse.

"Gary will never be forgotten," said Porter Fire Chief Jody Binnion.

Crews from area fire departments responded to the blaze after witnesses spotted smoke coming from the rear of the not-yet-opened business. Staley and the other firefighters were wearing full protective gear as they guided a hose inside the building. Binnion heard an explosion about a minute later.

"When I turned around, I saw the three guys crawling back out. They followed the hose," he said. "We don't know why or how Gary got separated from the other three guys."

After the flames were extinguished, Staley was found fewer than 20 yards from the hose that could have led him to safety.

"We train our guys strong and hard. They are smart firefighters," Binnion said."There's not a typical fire. It can happen anywhere at anytime."

A worker was laying tile in the building when the fire broke out. After cleaning the floor and applying adhesive for the tiles, he plugged in a heater and spotted a thin blue flame shoot from the wall socket.

"It was about the size of your finger. As he turned, the whole room was just engulfed in flames. All he could think about was just getting out," said the Rev. Mitchel Bell, a Porter minister who drove the man home after paramedics treated him for burns.

"He could see the flames but he could see through them. He ran out of the building," Bell said.

Neighbor Vernon Sutton dashed from his home after hearing the eruption next door.

"You could tell smoke was coming out of the building," he said. Even before fire crews arrived, Sutton spotted people pushing the company's classic cars away from the flames.

Like other Porter residents at the scene, Sutton mourned the loss of the hometown firefighter.

"It's bad for anybody to die, but it's one of the Porter boys, so that really makes it bad," he said.

In 1995, a Porter firefighter died of cardiac arrest while responding to a call, but Staley's death was the first fire-related fatality since the department was formed in 1962, officials said.

Staley worked in The Woodlands as an accountant for Anadarko Petroleum, but Binnion said he was devoted to his volunteer work.

"He was a strong guy (and) loved the Fire Department," Binnion said. "If we would have let him, he would have spent the night, every night up here at the station."

Staley was single and had an 8-year-old daughter, officials said