Two men who forced a terrified teenager to jump into a claypit pool and stoned him until he drowned were each jailed yesterday for 5½ years.

Shane Owoo, 16, was frogmarched to the “punishment swim” at Lunt Pool, in Bilston, West Midlands, on September 29 last year after being beaten up by Marvin Walker, 21, and Christopher Lewis, 22, because they believed he had stolen a bicycle.

The teenager, who was “not a natural swimmer”, was watched by around a dozen people as he tried to haul himself out of the pit only for his tormentors to push him back in by poking him with branches. Eventually, exhausted, he slipped under the surface of the chilly water and drowned.

The two men had pleaded guilty to manslaughter at an earlier hearing. At Birmingham Crown Court, Judge Peter Coulson told them that the situation had “escalated in a truly horrifying way”.

A third man, Tobias Davies, 21, also pleaded guilty to assaulting Shane and was sentenced to serve 12 months in prison. He walked free from court because he has already served 13 months behind bars on remand. The sentencing led to unruly scenes in the courtroom as the teenager’s family and friends fled the public gallery in tears. Several shouted abuse while one person yelled threats from beyond the dock’s protective screen.

The two men had hunted down the teenager to punish him for taking the bicycle. Davies had joined in as they punched, slapped and kicked their victim near a bus stop. Threats were made to kill Shane during the initial assault.

Then Walker and Lewis “frog-marched” the boy to the pool several hundred yards from his home, threw him into a nettle patch and ordered him to jump into the 10ft-deep water. He managed to stay above the surface for 20 minutes before he was overcome by exhaustion.

Anesta Weekes, QC, for the prosecution, described the two men, both from Wolverhampton, as “vigilantes taking the law into their own hands”.

She said: “He was forced to jump into the water and if he did not go in he would have been battered. He was ordered to swim and he tried.

“We say he must have been cold and frightened because, of course, he had already been beaten up and [knew] he was going to be punished. When he attempted to get back on to the bank of the pool, a branch was poked at him to prevent him from getting out. Gravel was kicked at him.”

About a dozen onlookers watched Shane struggle until one leapt in to try in vain to save him. Eventually Lewis followed suit with the same result. The teenager’s body was not recovered by police divers until the next day.

In a letter read out to the court Walker said that he was sorry for what he had done but Judge Coulson described their crime as “extraordinarily callous behaviour”.

Earlier, Pauline Fox, Shane’s aunt, had told the court that his family was still haunted by the manner of his death.

She told the judge: “He was a normal teenager, mischievous but helpful. He would always come into my shop and never left without giving me a hug and a kiss.

“We are struggling to come to terms with how Shane died. I do not think anybody needs to go through what he went through. It is something we are never going to get over.”

Judge Coulson said: “This was a long and terrifying ordeal deliberately inflicted on Shane Owoo. He was made to jump into the water in fear. He was not a natural swimmer.

“The fact that all these people were there and only one small boy tried to get Shane out is extraordinary.”

Outside the court, Detective Inspector Simon Richards, speaking on behalf of the family, said: “No sentence will bring Shane back. Nothing can help a family where a son and brother has been lost and unfortunately that is the position we have found ourselves in. It was a dreadful crime.”

Carol Lewis, Lewis’s mother, said: “I feel for Shane’s family. It is a tragedy. I hope they can one day forgive us for what happened.”

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