Relative: Mandela Signer in Group That Burned Men The bogus sign language interpreter at last week's Nelson Mandela memorial service was among a group of people who accosted two men found with a stolen television and burned them to death by setting fire to tires placed around their necks, one of the interpreter's cousins and three of his friends told The Associated Press Monday. But Thamsanqa Jantjie never went to trial for the 2003 killings when other suspects did in 2006 because authorities determined he was not mentally fit to stand trial, said the four. They insisted on speaking anonymously because of the sensitivity of the fake signing fiasco, which has deeply embarrassed South Africa's government and prompted a high-level investigation into how it happened. Their account of the killings matched a description of the crime and the outcome for Jantjie that he himself described in an interview published on Sunday by the Sunday Times newspaper of Johannesburg. "It was a community thing, what you call mob justice, and I was also there," Jantjie told the newspaper. Jantjie was not at his house Monday, and the cousin told AP Jantjie had been picked up by someone in a car Sunday and had not returned. His cellphone rang through to an automatic message saying Jantjie was not reachable. Instead of standing trial, Jantjie was institutionalized for a period of longer than a year, the four said, and then returned to live in his poor township neighborhood on the outskirts of Soweto. At some point after that, they said, he started getting jobs doing sign language interpretation at events for the governing African National Congress Party. Jantjie told the AP last week he has schizophrenia and hallucinated, seeing angels while gesturing incoherently just 3 feet away from President Barack Obama and other world leaders during the Tuesday ceremony at a Soweto stadium. Signing experts said his arm and hand movements were mere gibberish. In the interview last Thursday, Jantjie said he had been violent in the past "a lot" but declined to provide more details and blamed his violence on his schizophrenia, for which he said he was institutionalized for 19 months in a period that included time during 2006. The cousin and the three friends said the "necklacing" killing of the suspected thieves occurred within a few hundred meters (yards) from Jantjie's tidy concrete home near ramshackle dwellings. The four spoke to the AP on Monday in Jantjie's neighborhood, and one of the friends described himself as Jantjie's best friend. Necklacing was a method of killing that was fairly common during the struggle against apartheid by blacks on blacks suspected of aiding the white government or belonging to opposing factions. The method was also used in tribal disputes in the 1980s and 1990s. While people who encounter suspect thieves in South Africa have been known to beat or kill them to mete out punishment, necklacing them has been rare. An investigation is under way by South African officials to determine who hired Jantjie as the onstage interpreter at the Mandela memorial service and if and how he received security clearance. The officials have not said how long their investigation will take place, and reaching them for updates was difficult Monday, a public holiday in South Africa.