A sonic boom has rung out close to London after the RAF rushed to an incident.
A loud boom was heard across areas of Essex, Suffolk, and Cambridgeshire at around 11.30am on Friday morning.
The RAF confirmed that the sound was created by three Typhoon fighter aircraft that had been sent to investigate a civilian plane that was not in contact with air traffic control.
The flight which was travelling from Nice was escorted to Stansted Airport by the RAF.
A sonic boom sound rings out when an object moves quicker than the speed of sound.
The aircraft displaces the air and creates pressure waves that become compressed and are then released in a shockwave.
An aircraft flying at 20,000ft would create a sonic boom cone 20 miles wide.
An RAF spokesperson said: "We can confirm that RAF Quick Reaction Alert Typhoon fighter aircraft from RAF Coningsby were launched today to investigate a civilian aircraft which was not in contact with air traffic control, communications were re-established and the aircraft was safely escorted to Stansted.
"The Typhoons are returning to base."
People across parts of Essex reported hearing a loud bang after the jets were authorised to travel at supersonic speed.
Essex Police said: “A flight has been escorted into Stansted Airport after it lost contact with the ground.
“We were called at around 11.40am today.
“Contact was re-established with the plane, which had been travelling from Nice, and was escorted into the airport by RAF aircraft.
“On the ground our officers determined there was nothing of concern.”
