Police are investigating whether a tagging mission by a trio of graffiti artists ended in tragedy after three bodies were discovered beside train tracks in south London as the Monday morning rush hour began.

Paint spray cans were found near the bodies of three men believed to be in their 20s that were discovered at Loughborough Junction near a spot that is busy with freight trains overnight. It is suspected that the bodies had lain beside the tracks until they were spotted by a passing train driver in the morning.

Britain’s Press Association, citing rail industry sources, confirmed reports of spray cans being found near the site that is popular with graffiti artists. Police officers photographed various graffiti and sprayed tags (names) on the walls near to the site where the bodies were found but said it was too early to comment on the cause of death. Detectives are also investigating the possibility the trio killed themselves - but it appears unlikely, reported Mail Online.

Three People Die Pictured is a scene at Loughborough Junction where three people died after possibly being hit by a train on the tracks on June 18, 2018 in London. Photo: Neil P. Mockford/Getty Images All three men are believed to be in their 20s, Superintendent Matthew Allingham of British Transport Police said. Their deaths are being treated as "unexplained."

"Our investigation is focusing on how and why the men came to be on the tracks in the early hours of this morning," he said.

He added: "If someone was on those tracks there's nowhere they could go to avoid the train. They wouldn't have had much options."

Asked later about speculation they could have been graffiti artists, Allingham told BBC News: “It is one possibility, yes.”

The Mayor of London Sadiq Khan sent his condolences to the relatives of those found on the tracks. He said: "My heart goes out to the families of the three people killed at Loughborough Junction station this morning."