Aug 3 2012 By Alan Hayes
A Typhoon fighter jet roared off from RAF Northolt at about 4.40pm on Friday.
It was seen circling over the Ashford area a few minutes later, according to eyewitnesses on the ground.
The RAF has said that the Typhoons will only take off for security or engineering reasons.
An RAF spokesman said an aircraft had been scrambled in response to an alert, but there was no further detail at present.
5.05pm An RAF spokesman has confirmed the alert was a false alarm.