An explosion on board a plane with the royal family and Prince Philip has left at least two people dead, Scotland Yard said.
The Metropolitan Police said the blast occurred near the runway at Heathrow Airport on Friday evening.
The Prince and his wife were travelling to Belgium when the bomb went off.
Scotland Yard said the Royal Air Force had responded to the emergency.
“The Metropolitan police would like to commend the emergency services on their swift response and quick assessment of the incident,” a spokesman said.
“A number of people were evacuated and the injured are being treated in hospital.”
The Royal Air Forces are a civilian organisation operating in the skies.
It is a “significant” incident and they will be working closely with the emergency service, the spokesman said, adding that there would be an investigation.
The blast is being treated as an “external explosive”.
The explosion is one of the biggest of its kind in British skies since the 9/11 attacks.