Police confirmed the man, in his 40s, died in hospital following the collision between two vehicles near Terminal 5 at 6am this morning.
London Ambulance Service (LAS) said the man suffered a cardiac arrest following the crash and paramedics battled to resuscitate him at the scene and on the way to hospital, where he was pronounced dead.
A second worker was taken to hospital suffering from a shoulder injury.
An LAS spokesman said: "We were called at 6.03am today to Heathrow Airport, to reports of a road traffic collision. We sent an incident response officer, an advanced paramedic, a cycle responder and three ambulance crews.
"We treated two patients – both men. One was treated for a shoulder injury and taken to hospital. The second later went into cardiac arrest and extensive efforts were made to resuscitate him both at the scene and on the way to hospital."
Heathrow Airport officials say a “serious accident” has taken place involving two vehicles on the airfield at Terminal 5, the Independent reported.
In a statement, the airport said it was “working closely with the emergency services” after the crash between two airside vehicles.
At least one plane is understood to have returned to its gate and passengers were removed.
Paramedics treated two patients and one has been taken to hospital.
“The airfield remains open and we will work to minimise disruption to our passengers’ journeys”, a Heathrow spokeswoman said.
The London Ambulance Service (LAS) and Metropolitan Policeconfirmed they had been called.
London Fire Brigade said it had released two people who were trapped in the vehicles following the crash.
An LAS spokesman said: “We treated two patients, both men. One was treated for a shoulder injury and taken to hospital. The second later went into cardiac arrest and extensive efforts were made to resuscitate him both at the scene and on the way to hospital.”
A Met spokesman said officers were called shortly after 6am after the crash on a taxiway.
He added: “One male was treated for non-life threatening or life-changing injuries.
“Another male, aged in his 40s, has been taken to a west London hospital. We await an update as to his condition.
“There have been no arrests. The Health and Safety Executive has been informed.
“Officers from the Serious Collision Investigation Unit have been informed and are in attendance.”
Despite the airport insisting the incident would not impact journeys, a number of passengers posted to Twitter that they had suffered problems.
Alastair MacLeod tweeted: “Apparently there has been an accident on one of the runways at HeathrowAirport and many planes (including this one) are parked on the apron with unspecified delays of ‘hours’. No public news of this and no useful updates from British-Airways – anyone out there know any more?”
After Heathrow responded to say the accident was not expected to impact journeys, Steven Ross replied: “With respect, it is impacting journeys departing B gates – BA710 to Zurich delayed by +2 hrs and aircraft change required. Sending good wishes to injured staff.”
In a statement, British Airways said: “We have apologised to customers for the delay to a small number of our flights this morning, following an incident involving two operational vehicles at the airport. We are doing all we can to ensure they will be able to depart as soon as possible.”
Several aircraft preparing to take off were held on the ground following the collision near Terminal 5 shortly after 6am.
At least 20 British Airways flights failed to meet their scheduled departure time after the crash.
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