'Other acts of terrorism were planned'

Investigations

The guerrilla network that carried out the attacks on Washington and New York was planning to hijack at least one, and possibly several, more aircraft in what investigators and intelligence officials now believe was intended to be a multi-pronged assault on American targets lasting several days.

The Chicago Tribune reported yesterday that the Federal Bureau of Investigation was looking closely at the passenger list for American Airlines flight 43, which was due to leave Boston for the west coast 25 minutes after the first plane, which ended up crashing into the World Trade Centre.

Flight 43 never left the ground because of a mechanical problem. The FBI told the paper that a small group of men on the passenger list never returned for a later flight once commercial flying resumed late last week. They are now considered possible suspects.

The FBI is also looking at a number of other flights already in the air when the World Trade Centre and the Pentagon were hit. The agency did not say how many planes were under scrutiny, but Vice-President Dick Cheney said at the weekend that the White House was told as many as six rogue aircraft were in the sky at some point last Tuesday morning. The hypothesis is that other hijacking teams had to abort their plans after planes were grounded by the Federal Aviation Authority.

Evidence of further planned mayhem was bolstered yesterday by Bob Graham, chairman of the Senate Intelligence Committee, who said the attacks might have been the start of a sustained assault on US interests. Senator Graham told the Orlando Sentinel: "There has been very credible evidence gathered since Tuesday that Tuesday's attacks were not designed to be a one-day event. There were other acts of terrorism in the United States and elsewhere that were part of this plan ... Not necessarily hijacking another airliner, but maybe putting a chemical in a city's water system, or blowing up a bridge in a major urban centre," he said.

US officials have warned repeatedly that more attacks might be on the way. An FBI list of possible associates of the hijackers includes five people with seats on a United Airlines flight to Denver this Saturday, the Los Angeles Times reported yesterday. One of the five is being questioned in New York. The flight, meanwhile, has been cancelled – for business rather than security reasons.