He was released just moments ago. He is of no investigative interest to the FBI

FBI spokesman Joe Valiquette

Flight 101 was intercepted by US and Canadian fighter jets on its way from London after officials at Heathrow reported - following the flight's departure - that the man might be on a terrorist watch list.

The suspect was removed from the plane shortly after it landed without incident at 1645 EST (2145 GMT) and the plane was then allowed to taxi into the terminal.

Security has been beefed up in the wake of 11 September

Air security officials around the world have been on heightened alert since 11 September last year, when hijackers flew jets into the World Trade Center and the Pentagon, killing about 3,000 people.

FBI spokesman Joe Valiquette said the man was a British citizen and was travelling with a woman, who was also escorted off the plane. Reports say the man has an Arabic name.

'Confrontation'

The first time I knew something had happened was when the captain came on and said, 'Sorry for the delay. The police are coming on to escort someone out

Brett Gascoine, passenger

New York Police Commissioner Raymond Kelly said that there had apparently been "some sort of confrontation" between one of the two passengers and a security screener at Heathrow.

The screener had said: "'This individual looks like somebody who may be wanted' - or words to that effect," Commissioner Kelly told journalists.

"That's what has triggered this alert."

Scotland Yard has confirmed that police questioned a man at Heathrow Airport, but that the passenger was allowed to continue his journey.

The flight was intercepted by Canadian jet fighters about 200 miles (320 km) off the coast. US fighters took over when the airliner entered US airspace.

Passengers unaware

Officials say there was no disturbance and no fear of a hijacking on the plane, which started its journey in Bombay and was carrying 378 passengers and 19 crew.

Crew members were notified, but were not alarmed. The plane was fitted with a reinforced cockpit.

Upon its arrival at JFK airport, the plane was diverted to a secluded area and surrounded by about a dozen police vehicles.

Passengers aboard said they did not notice anything unusual until the plane landed.

"The first time I knew something had happened was when the captain came on and said, 'Sorry for the delay. The police are coming on to escort someone out,'" said Brett Gascoine, from Britain.