A sonic boom has been heard and felt by residents in London, Essex and Cambridge after two RAF fighter jets were scrambled to intercept a private plane.
The jets were scrambled from RAF Coningsby in Lincolnshire to intercept the plane – which had lost communications and was escorted to London’s Stansted Airport.
Flight tracking website ADSBexchange.com recorded a Eurofighter Typhoon FGR4 reaching a peak speed of over 1,000 knots (1,150mph) above Ickleton, just south of Cambridge.
A sonic boom is the sound associated with the shock waves created whenever an object travels through the air faster than the speed of sound, 767mph, which the jets first surpassed near Peterborough.
The website later showed that the fighter jet had returned to RAF Coningsby.
Cambridge City Council tweeted telling residents not to panic.
"If you heard a massively loud bang over Cambridge in the last few minutes, don't panic - apparently it was the sonic boom from a fighter plane breaking the sound barrier!" The council wrote on Twitter.
Another Twitter user posted a video in which an explosion could be heard.
An RAF spokesperson said: “The RAF can confirm Quick Reaction Alert Typhoon aircraft were launched this afternoon from RAF Coningsby to intercept a civilian aircraft that had lost communications; subsequently, communications were re-established, the aircraft was intercepted and safely escorted to Stansted.
“The Typhoon aircraft were authorised to transit at supersonic speed for operational reasons.”
The jets are often deployed to escort aircraft that lose contact with air traffic control or don’t respond to communications.