N.Y. Airport Target of Plot, Officials Say

"We have pretty extensive security and safety features on that pipeline system," said Roy Haase, a spokesman for Buckeye, which owns approximately 5,400 miles of pipelines in the Midwest and Northeast.

Haase said that the fuel tanks at the airport are separated from the pipelines by cutoff valves and that even if a fire broke out at the tanks, it would not back up into the pipelines. "The pipeline is completely full of liquid so there's no oxygen in it," Haase said. "To say that the pipeline would blow up is just not possible."

Fuel tanks at airport are in two clusters, removed from main passenger terminals and runways.

An explosion there "may not cause a lot of deaths, but it would be spectacular and seen around world," said John W. Magaw, a former head of the Transportation Security Administration. "It could cripple the airlines."

The last major fuel tank fire at an airport that federal investigators could recall took place in 1990 at Denver's old Stapleton International Airport. It took more than 600 firefighters to extinguish the blaze, which burned for two days and snarled air traffic. More than 3 million gallons of fuel were lost to the fire or leakage from the tanks, at a cost of between $15 million and $20 million, but no one was injured, according to the National Transportation Safety Board.

According to the complaint, Defreitas stressed JFK's symbolic significance as a terrorist target.

"Anytime you hit Kennedy, it is the most hurtful thing to the United States. To hit John F. Kennedy, wow. . . . They love John F. Kennedy like he's the man. . . . If you hit that, the whole country will be in mourning. It's like you can kill the man twice," he said in a recorded conversation with the source.

Mufson reported from Washington. Staff writers Spencer H. Hsu, Ann Scott Tyson and Del Quentin Wilber and researcher Magda Jean-Louis contributed to this report.