A stowaway fell from a plane’s landing gear as it approached Heathrow Airport and was found dead in a garden after landing “one metre” from a sunbather.
The man’s body was found in Offerton Road in Clapham, south London on Sunday afternoon, police said.
A neighbour said he heard a “whomp” and went to look out of an upstairs window.
The body had “all of his clothes on and everything” but on closer inspection there was “blood all over the walls of the garden”, he said.
The body was “so intact” because it was “an ice block”, the man added.
He continued: “His head was not in a good way. I realised immediately that he had fallen.
“So I went outside and it was just then the neighbour came out and he was very shaken.
“He had been sunbathing and he landed one metre away from him.”
The neighbour said a plane spotter who had been following the flight on an app from Clapham Common had seen the body fall.
The spotter, who arrived at almost the same time as police, told officers it had been a Kenya Airways flight.
Officers are trying to identify the man who fell from the plane.
He dropped from the aircraft at the end of a nine-hour flight from Nairobi.
A bag, water and food were found in the compartment containing the plane’s landing gear.
A post-mortem examination will be carried out, but the death is “not being treated as suspicious”, Met Police added.
The body was removed at about 8.30pm and the clean-up team returned on Monday morning, the neighbour said.
In a statement, officers said “police believe the man was a stowaway and had fallen from the landing gear of an inbound Kenya Airways flight to Heathrow Airport”.
Officers will be liaising “with the airline and international authorities”.
Although a rare occurrence, it has happened before.
In September 2012, a 30-year-old man from Mozambique, Jose Matada, died after falling from the undercarriage of a flight approaching Heathrow from Angola.
He is believed to have survived freezing temperatures of up to -60C (-76F) for most of the 12-hour flight, an inquest heard.
But by the time he hit the ground he was “dead or nearly dead”.
In 2015, the body of a man landed on a shop in Richmond, southwest London, after travelling in the undercarriage of a plane from Johannesburg.