LONDON (AP) — Police believe he was from Africa, probably from Angola, but they don’t know his identity.

The mystery began in September when residents of a suburban street in the Mortlake neighborhood of West London woke up on a quiet Sunday morning to find the crumpled body of a black man on the sidewalk of Portman Avenue, near a convenience store, an upscale lingerie shop and a storefront offering Chinese medical cures.

Detectives believed at first the man was a murder victim and cordoned off the area. Within a day, however, police concluded the man — probably already dead — had fallen to the ground when a jet passing overhead lowered its landing gear as it neared the runway at nearby Heathrow Airport.

The apparent stowaway had no identification papers — just some currency from Angola, leading police to surmise that he was from that African nation, especially as inquiries showed that a plane from Angola was beginning its descent into Heathrow at about that time.

The macabre explanation made perfect sense to residents, who are familiar not only with the roar of the jets descending, but are also able to see the planes lower their landing gears as they pass overhead, said Catherine Lambert, who lives a few doors down from the spot where the man landed.

“You could see him, his body was contorted,” she said. “It was a beautiful blue day, really sunny, but we had to keep the children inside. I didn’t want the children to see, and to have to explain to them and put fear into them every time a plane goes over.”

A post mortem conducted two days after the body landed listed the cause of death as “multiple injuries.”

In the days afterward, some neighbors put flowers on the spot where the stowaway was found, and a small group of Angolans who live in the London area came to place more flowers and to pray. Lambert, 41, said there is lingering sadness, since the man has not been identified and there has been no way to tell his family he is gone.

“I felt, what was he running away from? What made him think he could he could? And how will his family ever know? He’s a lost soul now; his father and mother are probably waiting for him to make contact,” she said.

A London police spokesman, who wasn’t authorized to speak on the record because of force policy, said Sunday that police are appealing to the public for help identifying the man based on a composite image of his face and a photo of a tattoo on his left arm. The tattoo showed the letters “Z” and “G” inked on his upper arm, with a horizontal line through the “Z”.

Police also said attempts to identify the man with the help of Angolan authorities had been unsuccessful. They stressed there is only “circumstantial” evidence linking the stowaway to that country.

In a statement, police said the man is believed to be an African of slight build between the ages of 20 and 30. He was wearing jeans, white sneakers and a gray sweatshirt when he was found on Sept. 9, police said.

Although firm figures are not available, in recent years there has been a rise in the number of stowaways trying to get to Western Europe by hiding in the undercarriages of passenger planes.

Aviation safety specialist Chris Yates of Yates Consulting said Sunday that poor airport perimeter security at a number of airports in Africa — including the main Angola airport at Luanda — and in other parts of the world has made it easier for people to stow away on planes, but that most attempts fail.

“They so often end in fatality because more often than not stowaways climb into the wheel base or cargo hold, and those areas are not necessarily pressurized,” he said. “When you start moving beyond 10,000 feet, oxygen starvation becomes a reality. As you climb up to altitude, the issue becomes cold as well, the temperature drops to minus 40 or minus 50 degrees centigrade, so survival rates drop.”

He said the man who crashed to the pavement in Mortlake had probably lost consciousness and died within the first hour of his flight.

Police said the body is being held for possible repatriation in case the man’s identity is established.

Mortlake residents and business people speak of a similar death in recent years, but disagree about the timing and the details.

“People say the same thing happened a few years ago a few blocks away” said Jay Sivapalan, 29, who works at the Variety Box convenience store half a block from where the body landed. “We are near Heathrow and when they lower the landing gear, the body falls out.”

Others believe the incident may have happened 10 years ago. Police said they had no information about other stowaway deaths.

Copyright 2012 The Associated Press.