10/31/99 -- 9:51 AM FAA issued unconfirmed bomb alert for New York, Los Angeles WASHINGTON (AP) - A month ago, the Federal Aviation Administration issued an alert to airline and airport security personnel after agencies received an unconfirmed warning that a bomb would ``soon be used'' on a flight departing from Los Angeles or Kennedy airport in New York. Officials said they had no reason to believe the disappearance of an EgyptAir flight on Sunday was caused by sabotage. Investigators were attempting to determine the fate of Flight 990 after takeoff from Kennedy International Airport. The flight originated Saturday in Los Angeles. Many aviation warnings are investigated each month by federal agencies and the Sept. 24 alert said: ``At this time, FAA has no information to corroborate the statements in the letter and assess them as lacking credibility.'' Asked about the alert, David Leavy, spokesman for National Security Council, told The Associated Press, ``I don't want to speculate on this until we have information.'' A U.S. intelligence official said at midmorning Sunday that agencies were pursuing the possibility of sabotage, but, ``There's nothing to immediately point toward that.'' Another official said there had been no recent threat that seemed relevant to the EgyptAir disappearance. In a Sept. 24 ``information circular,'' the FAA said several U.S. agencies received a warning by letter in August ``that a bomb or explosive device with `spiral expansion' would soon be used on a flight departing from either Los Angeles airport or New York's JFK airport.'' The circular said the informant ``identified himself as Luciano Porcari,'' and noted that ``an individual with this same name hijacked an Iberian Boeing 727 during a flight from Barcelona to Palma de Mallorca, Spain, on March 14, 1977,'' before being overpowered and arrested. The alert said the writer said ``three of these devices were smuggled into the United States between 1992 and 1993, and that the devices cannot be detected on a metal detector because of the PVC (plastic) composition.'' The alert was in effect until Oct. 30. EgyptAir Flight 990 departed Los Angeles on Saturday, Oct. 30, and stopped at John F. Kennedy International Airport, bound for Cairo. The plane took off from JFK at 1:19 a.m. Sunday en route to Cairo and disappeared from radar screens about 40 minutes later. At a news conference in Cairo, the head of EgyptAir, Mohammed Fahim Rayan, said he had no information of any direct threat against his airline. Last month, the FAA offered no comment on its alert. ``The FAA often sends out information on threats to ensure that airlines can properly implement security measures,'' agency spokeswoman Rebecca Trexler said at the time. ``We do want to assure the public that the FAA works with law enforcement and intelligence agencies of the United States and other countries and we closely evaluate all threats and take appropriate security measures as warranted,'' Trexler added. The FAA circular said a Luciano Porcari was sentenced to 10 years in prison on Jan. 25, 1979, but later escaped. In August 1981, he threatened to hijack another aircraft unless he was paid $250,000. He was subsequently arrested in Italy and sentenced to nine years in prison on Jan. 27, 1982. The circular said he was released on Aug. 12, 1982, and his whereabouts were unknown. In the warning received by letter ``to several U.S. government agencies,'' the informant ``claimed that between 1975 and 1983 eight of the devices were manufactured, that only three remained and that one was in the U.S. He also said he had warned various U.S. authorities about the device before the July 1996 explosion of TWA Flight 800 off Long Island and the September 1998 crash of Swissair Flight 111 off Newfoundland. The TWA plane had taken off from Kennedy airport en route to Paris, while the Swissair plane had taken off from Kennedy en route to Geneva. After an extensive investigation, authorities ruled out a criminal act in the TWA crash. They now believe there was an explosion for an undetermined reason in the plane's center fuel tank. The Swissair plane crashed 16 minutes after the pilots reported smoke in the cockpit. Authorities have not determined a cause but are focusing on the airplane's wiring and insulation material.