A gunman who hijacked a fuel truck at National Airport on Tuesday night and shot two workers could have driven onto runways that were in use or into fueling areas, an airport spokesman said.

The suspect, identified by police as Jeffrey Garland, 29, of Woodbridge, was arrested about 10:30 p.m. aboard an airport parking shuttle bus after abandoning the truck.

"It was fortunate he didn't kill anybody," said Dave Hess, airports authority spokesman, who acknowledged that nothing stood between the gunman and the busy airport's runways.

An airport maintenance worker, who was familiar with the incident but did not want to be identified, said an armed hijacker driving a fuel truck unrestricted on airport grounds could have led to a catastrophe.

"Everyone was just really lucky this didn't turn out to be a . . . tragedy," the worker said. "If he'd wanted to blow up some fuel or get to the runways, he could have."

The wounded men are employees of Ogden Allied Services, a company that fuels airliners at National. Garland worked for Ogden until last May. Ogden officials would not comment.

Authorities said the incident began when Garland, who officials said left his job at Ogden by his own choice, walked with a gun into Ogden's maintenance facility at the south end of the airport.

Officials said the suspect locked two Ogden employees in a room and forced a mechanic into a fuel truck. The gunman told the mechanic, whom authorities did not identify, to drive along Thomas Avenue to an electric security gate that restricts access to National's runways, hangars and fuel facilities.

Using the mechanic's security card to open the gate, the gunman had the mechanic drive into the secured area before telling him to get out of the fuel truck. The mechanic ran to alert police.

Hess said three Ogden employees in a van noticed the gunman driving "faster than normal" on the apron near the airport's south hangars and brought the fuel truck to a stop by blocking its path. Still inside the truck, authorities said, the gunman opened fire on the three men in the van, wounding two of them.

The wounded were identified by airport officials as Anthony Andrew, a supervisor at Ogden, and David Harley. The exact nature of their wounds was not released, but neither was seriously injured.

Harley was treated at the National Hospital for Orthopedics and Rehabilitation in Arlington and released.

Andrew was treated there overnight before being released yesterday, officials said.

After the shootings, the gunman ran from the secured area back to Thomas Avenue, where he caught the parking shuttle bus. The bus driver noticed that the suspect had a gun, and jumped out of a window seconds later, officials said.

Officials said they did not know whether any passengers were on the shuttle bus. The driver, whose identity was not made public, was treated at the same hospital for a bruised shoulder and released.

By the time the driver escaped the bus, airport police officers who had been alerted by the Ogden mechanic had caught up with the suspect.

Garland was arrested at the bus without incident, officials said. He was charged with abduction, two counts of malicious wounding and unauthorized use of a vehicle.

He was being held at the Arlington County jail yesterday under $100,000 bond.

After he was arrested, airport police found Garland's blue Ford Mustang in an employees parking lot at National. Inside were several "molotov cocktails," said officials. They said Garland could face additional charges involving the explosive devices.

Airport officials said the incident did not affect operations at National.

"Apparently he didn't get too far," Hess said of the gunman. "There were no aircraft where he was, certainly no large aircraft."

If the gunman had driven the truck outside of marked vehicle lanes in the runway area, he likely would have been noticed immediately by airport ground workers, who could have notified the control tower by radio, Hess said.

He said the incident is an indication of the limits to airport security.

"I have a card that gets me into certain places, and if someone came up to me and pulled a gun, there's not much I could do," Hess said.