Berlin, June 12: Osama bin Laden's al Qaeda network may be planning to use model airplanes to attack passenger aircraft worldwide, a German security source said on Wednesday.

The security source said the warning had come from Germany's BND intelligence agency and was based on information from the United States. The source said the agency had warned that al Qaeda guerrillas could strike at passenger aircraft using radio-controlled model airplanes or small rockets.

"The information came from the United States. It could happen anywhere in the world," the source told Reuters, adding that the threat was being taken seriously despite its unspecific nature.

"The information should be treated with caution," he added.

The FBI warned law enforcement agencies in the United States in May that al Qaeda may possess shoulder-fired anti-aircraft missiles.

Germany's mass-circulation Bild newspaper, citing a BND document based on intercepted radio messages, reported earlier Wednesday that the BND warning focused on an attack on aircraft at Frankfurt or another major German city.

However, the German criminal agency LKA in the federal state of Hessen, where Frankfurt is located, said the BND warning was not specific. There was no concrete evidence of any forthcoming attack, an LKA spokesman said.
German Chancellor Gerhard Schroeder said Tuesday the government too had no evidence of an immediate threat of attacks by al Qaeda on Germany.

Germany has played a central part in the investigation into the September 11 suicide plane attacks on U.S. cities, which Washington blames on al Qaeda. Three of the four suspected hijackers, including Mohammed Atta, their alleged ringleader, lived for years in the German port city of Hamburg. Bureau Report