Officials said the man who died was a British Airways worker
A man has died following a "serious accident" on the airfield at London's Heathrow Airport.
Police and paramedics were called to the scene of the incident shortly after 6am on Wednesday morning, which the airport has said involved two male members of staff.
London Ambulance Service confirmed that one of the men, who was in his 40s and worked as an engineer for British Airways, went into cardiac arrest.
Despite "extensive efforts to resuscitate him" at the scene and on the way to a west London hospital, he was later pronounced dead.
A Heathrow spokesperson said:
Following a serious accident involving two vehicles on our airfield, a British Airways colleague has passed away. Our deepest condolences go to the family and friends affected by this accident.— Heathrow Airport (@HeathrowAirport) February 14, 2018
We will be fully cooperating with the Police in the investigation which will follow.
A British Airways spokesman added: "We are deeply saddened by this tragic incident and are offering our full care and support to his family and colleagues."
The other man involved in the accident suffered a suspected broken shoulder and was also taken to hospital.
Officials said his injury was "not life-threatening or life-changing".
Some passengers were forced to leave their planes as a result of the incident, with delays to a number of flights reported by people on the tarmac and at their gates.