An RAF fighter jet tasked with defending the Olympics against terror attacks was scrambled on Friday after an aircraft lost contact with aviation authorities, the Ministry of Defence said.
The Typhoon was sent to intercept the aircraft after air traffic controllers lost contact.
But the jet was able to return to its base at RAF Northolt, west London, shortly after taking off when communication was re-established with the pilot.
An MoD spokesman said it was at least the third time Typhoons have been scrambled since the start of the Olympics on July 27.
He was unable to confirm the type of aircraft involved in this latest incident but said it was flying outside London's restricted flying zone.
Four Typhoon jets are on standby to intercept aircraft suspected of posing a terror threat throughout London 2012.
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