Heathrow security scare as man walks on runway

A man was arrested by armed police at Heathrow yesterday after he managed to dodge security and sprint on to one of the runways. The intruder, who reportedly scaled a perimeter fence before reaching the airport's north runway, was clutching a bag.

Witnesses said the man threw the bag aside as he ran towards a plane on the runway, before he was surrounded by armed police. He is now in custody. A controlled explosion on his bag revealed it contained no explosives.

The incident, which took place shortly after 2pm, is the second major security breach to take place at the airport in 18 days. It is believed that the interloper may have been trying to cause disruption ahead of the Queen's arrival at the airport's official opening of its fifth terminal today, before it opens to the general public on 27 March.

Scotland Yard said that anti-terrorist officers had been made aware of the incident but it was being dealt with by local police at the airport. A Metropolitan Police spokesperson said: "A man was arrested and is currently in custody. A bag has been recovered." The airport was undergoing security tests in preparation for the Queen's visit, which Buckingham Palace said yesterday would go ahead as planned.

Police and fire appliances sped to the scene when the intruder was spotted, and officers were seen holding him face-down in the grass at gunpoint.

A spokesman for BAA Heathrow said: "Airport police swiftly apprehended a man near the northern runway of Heathrow this afternoon. The police arrested the man at about 2pm within the airport perimeter.

"Some short delays have occurred as a result but we expect to return to normal later this afternoon. Clearly this incident is a matter of some concern and will be fully investigated in conjunction with the police."

The northern runway was temporarily suspended while police dealt with the incident, which ended just before 4pm, when the runway was brought back into use. The southern runway remained fully operational throughout the incident.

One theory for the security breach is that the man was making a last ditch protest at the environmental implications of a fifth terminal before today's opening ceremony. But environmental groups that have previously campaigned on the issue have since distanced themselves from the security breach.

A spokesperson for the anti-airport expansion group Plane Stupid, which recently breached Westminster security to protest against the airport's new terminal, categorically denied any involvement in the incident.

"I'd be amazed if it was a protester as that's really dangerous," said a spokesperson. "It doesn't sound like an environmental protest – if it was, he didn't get his message across well".

Greenpeace also said they were mystified by the incident yesterday, saying they had "no idea" why it had taken place. They were the most recent campaign group to penetrate Heathrow's security, when activists walked on to the runway last month and climbed on to a Boeing 777, unfurling a protest banner over the aircraft's tailfin.

Gordon Brown said yesterday that he was satisfied that everything was being done to maintain security at Heathrow.

Speaking after arriving at a European Union summit in Brussels, Mr Brown said: "I think the important thing about the Heathrow incident is that the person was detained, that all the security precautions went quickly into action, that he's now being interviewed and that all possible steps were taken so that when this incident happened the arrest took place."