The British government has warned the aviation industry of a possible al Qaeda attack, security sources and the BBC said on Friday. The BBC said it had obtained a letter from the Department of Transport addressed to the air transport sector, which explained the reason for heightened threat.
"There are indications that al Qaeda may be considering an attack against a UK airport or aviation sector target," it quoted the letter as saying. "The economic, political and psychological significance of the UK aviation sector coupled with the large crowds present within some of its major assets would enable a successful attack to fulfil al Qaeda's objectives."
Counter-terrorism advice to the transport sector had updated the threat to "severe", meaning an attack was considered highly likely, a British security source told Reuters, although there was no intelligence of any imminent assault. Britain's national threat level has been at severe for a year and officials played down the significance of the change for airports and railway terminals, indicating it was a precautionary measure.
The BBC said the letter emphasised that no changes to security measures had been made as a result and that the planned method of attack was unclear. An American intelligence official said US authorities were aware Britain had raised its threat alert level for transport hubs but added there was little indication of any increased threat to the United States.
The official, speaking on condition of anonymity, told Reuters that British authorities had taken the action based on recent intelligence reporting which suggested increased threats against transport targets but was vague regarding timing or tactics of any possible attack. "The government has made no secret of the fact there's an ongoing threat of a Mumbai-style attack by al Qaeda which has been threatened across Europe," a British government source said.