An Air India passenger plane was forced to make an emergency landing at Stansted Airport after a bomb threat.
The Boeing 777 airliner was escorted into London by two RAF Typhoon fighter jets.
The RAF confirmed it had scrambled the jets due to a bomb scare on board.
Air India posted in a now-deleted tweet that it had made the precautionary landing in London due to a “bomb threat” shortly before 10.30am today.
The airline later said the bomb scare was a hoax call received at Mumbai Airport, adding there was no security risk.
A sonic was widely felt and heard boom in Derby around the same time.
An RAF spokesman said: “The RAF can confirm QRA Typhoons were launched this morning from RAF Coningsby to intercept a civilian [aircraft].
“The aircraft was escorted to Stansted. The Typhoons transited at supersonic speed for operational reasons; any inconvenience caused to local residents is regretted.”
Essex Police said they are at the airport making enquiries after reports of a security alert.
Stansted Airport released a statement confirming the Air India Boeing 777 had been diverted at 10.15am and had “landed safely with Essex Police in attendance.”
A spokesperson tweeted: “It is parked on an isolated stand away from the normal airport operations.
“Our runway has now re-opened and is fully operational. We are very sorry for any delays and disruption caused by the incident, but our first priority is always the safety of passengers and staff.
“Thank you for your patience.”
The Air India aircraft had been heading from Mumbai to Newark.
The airport added shortly before 11am that its runway had reopened and is fully operational
We are sorry for any disruption caused by the incident and would like to thank you for your patience,” Stansted tweeted.