A man armed with a handgun was shot by officers using a Taser stun gun at London's Gatwick Airport, police said today.

The man, aged in his 40s and from the town of Crawley near the airport to the south of London, had got on board a bus to Gatwick shortly before 2 a.m., Sussex Police said.

When he arrived at the airport he was confronted by armed police on routine patrol who disarmed him using a Taser.

"Such incidents are rare and the speed and professionalism in which it was resolved meant that no one at the airport was harmed," said Chief Superintendent Paul Morrison.

A police source said the incident was not terrorism-related and it was not yet clear if the gun was real or an imitation.

"There is no suggestion, at this stage, that threats were made to passengers or aircraft," said Geoff Williams, head of security at the airport.