On Thursday, the police said they had solved at least part of the mystery, when fingerprints taken from the hand of the decomposed body showed that he was Sebastiano Magnanini, 46, an Italian carpenter living in South London and one of the men behind the brazen theft almost 22 years ago of a masterpiece from an unguarded church in his native Venice.
During their escape, the canvas fell on the ground, unrolling itself, and the three men picked it up and secured it with a shoelace.
London’s Metropolitan Police said on Thursday that a post-mortem examination had taken place. The cause of death was not yet known. The police said they were treating it as a suspicious death. A Scotland Yard spokesman said on Thursday night that Mr. Magnanini’s past in Italy would form part of the investigation, and that organized crime was not a line of inquiry at this point.
In addition to the tattoo on his shoulder, he had one of a koi carp on his torso and several others on his hand, the police said.
Before going to London last year, he lived in Colombia, Thailand and Cambodia. In London, he worked building sets for theater and other event companies.
The police said they became aware of the death after a passer-by spotted the body on Sept. 24 in Regent’s Canal in north London, a scenic and verdant spot peppered with houseboats, public housing and new expensive glass lofts.
Detective Chief Inspector Reeves, said that Mr. Magnanini had taken public transportation to central London two days earlier, before he disappeared. “This has been devastating for Sebastiano’s family,” she said.