LONDON — British transport authorities have warned aviation officials that Al Qaeda is considering an attack against a United Kingdom airport or other airline industry target in a threat described as credible, the BBC reported yesterday.
The warning, delivered in a letter, went on to say that no changes to security will be made and the planned method of attack is unclear. Transport officials declined to comment or say when the letter was sent, though they issued a statement saying transport security “is kept under constant review.’’
The BBC report was delivered amid heightened concerns at airports and railway stations. British Transport Police declined to comment on the deployment of officers and said the public would not notice significant changes.
However, the police denied a Sky News report that officers had been ordered to cancel days off.
A government security official, speaking on condition of anonymity because of the sensitivity of the issue, said the heightened awareness came from increased “chatter’’ among suspects under surveillance by the authorities, but that no threat was imminent.
Britain’s government said the overall threat level from international terrorism remains at “severe’’ — the second-highest level, meaning an attack is highly likely. The level has not changed since January 2010.
Britain’s Home Office said that any imminent, serious threat to public safety would prompt a change in the overall threat level — and would see it raised to “critical’’ on the system’s five-point scale.