A body spotted plummeting from a jumbo jet on to a runway at Gatwick Airport is thought to be the

second to fall from the undercarriage of a plane in two days.

Police believe the victims could have been stowaways who clambered into the underbellies of planes to travel for free in freezing conditions. They have not ruled out the possibility the deaths were linked.

The body of a man in his 20s was found at 9.25am yesterday after an airport worker saw something fall from a plane.

The discovery followed another body of a man in a field on the West Sussex border the day before. Police suspect he too may have fallen from a plane heading in or out of Gatwick.

Yesterday's tragedy is believed to have involved a British Airways 777 heading for Cancun in Mexico.

Officers are struggling to identify the man as he carried no identification. They do not know if he was killed by the fall or died during a previous flight into Gatwick.

Inspector Martin Pattenden, leading the latest investigation, said: "It is very unlikely he had fallen out of a cabin or from inside the plane, so I can't think of any other reason he would be in that part of an aircraft.

"It's a possibility he may have flown in from somewhere else, but to be honest we just do not know."

Flights were disrupted for nearly an hour while a team of more than a dozen officers sealed off the runway before moving the body.

One incoming Virgin flight was diverted to Heathrow and a queue of planes built up above Gatwick until control staff finally gave them permission to land.

Airport staff said the disruption was kept to a minimum, particularly because there were few people travelling on Christmas Day.

Sussex Police have teamed up with officers from the Surrey force who are investigating the death of the first man who was found in a field near Rudgwick on the border of West Sussex and Surrey.

Gatwick Airport's duty manager, Mike Ingle, said the two deaths were highly unusual but there was no firm evidence to suggest they were linked.

He refused to comment on whether either man could have slipped through airport security.

It is not the first time bodies have been discovered. Three years ago a young stowaway died during a flight from Africa.