LONDON – The suburban stillness of the comfortable, two-story homes in west London’s Mortlake neighborhood is broken only by the roar of jets thundering overhead on the final approach to Heathrow Airport. It’s a pleasant place, with easy connections into central London, generally free of crime and congestion.

That changed early on a sunny Sunday morning in September when a man from Africa literally fell from the sky and landed with a loud thud onto the sidewalk of Portman Avenue, half a block from a convenience store, an upscale lingerie boutique, and a shop selling Chinese herbal remedies.

In the hours after the crumpled body was found, as early risers were getting up to walk their dogs, get the papers, or go to church, police thought the man was a murder victim. But it was soon determined that he had been a stowaway who fell from a passenger plane when it lowered its landing gear directly above Portman Avenue.

“It was scary, there was a body on the street, and nobody knew at first that he had fallen from a plane,” neighbor Stephanie Prudhomme said.

The identity of the man remains a mystery three months later. He carried no identification, but police believe he may have been from Angola. They are asking the public to help identify the man, whose death has traumatized the neighborhood.

Police came to believe the man stowed away on a passenger jet bound from Angola to London.

“There is great sadness,” said Catherine Lambert, who lives a few doors down from the spot where the man landed. “To think that the end of the line for him is a suburban street, miles away from his world.”

The event shattered the neighborhood’s sense of being immune from the world’s troubles, she said, a feeling compounded by the inability of police to identify the man.