The schizophrenic sign language “interpreter” who failed to relay a single real word while standing just inches from President Obama at Nelson Mandela’s memorial has a violent rap sheet including murder, rape and kidnapping charges — and South African officials have no clue how the guy got on stage.

Thamsanqa Jantjie, who outraged deaf people with his hand-flapping gibberish on Tuesday, faced attempted murder and kidnapping charges in 2003, according to the South African TV news outlet ENCA. He was also charged with rape in 1994 and convicted of theft in 1995, the station reported.

It’s unclear whether he did time for the crimes likely because he was “mentally unfit” to stand trial, the station reported.

The South African government is still scratching its head over how Jantjie — who admitted he hears voices and “saw angels” soaring into Johannesburg’s FNB Stadium — was chosen to interpret speeches for world leaders at the globally televised memorial, said Phumla Williams of the country’s government communications office.

A top United States official called the crazy interpreter’s proximity to Obama disturbing.

“We’re all very upset,” the official said.

Linda Thomas-Greenfield, U.S. Assistant Secretary of State for African Affairsin Kenya , added American officials are concerned about security and how he could have gotten so close to world leaders.

Vetting for criminal history and other background checks for people onstage at the memorial were the responsibility of the South Africans, Secret Service spokesman Ed Donovan said on Thursday.

He added that Secret Service agents are “always in close proximity to the president.”

Jantjie declined to comment on his criminal history.