Reports that the bogus sign language interpreter at Nelson Mandela's memorial once faced a murder charge are being investigated by t he South African government.
Spokesman Phumla Williams said it is looking into how Thamsanqa Jantjie was selected to interpret at the memorial on Tuesday at which he stood close to US president Barack Obama and other leaders.
Mr Jantjie outraged deaf people by making signs they said amounted to gibberish. A South African TV news outlet, eNCA, is reporting that Mr Jantjie faced a murder charge a decade ago, but it is unclear if the case was concluded. He also reportedly faced other criminal charges.
Asked by an Associated Press reporter about a murder charge, Mr Jantjie turned and walked away without commenting.
A top United States official said "we're all very upset" about the bogus sign language interpreter who appeared just three feet from Mr Obama at the memorial ceremony for Mr Mandela, who died in his Johannesburg home on December 5.
US Assistant Secretary of State for African Affairs Linda Thomas-Greenfield told reporters in Kenya today that officials are concerned about security and how the interpreter could have got so close to world leaders.
Mr Jantjie said on Thursday he has been violent in the past and hallucinated during the memorial service as he was gesturing incoherently.
Ms Thomas-Greenfield also said officials are dismayed because the people who need sign language weren't able to understand what was said at the ceremony. She called the problem "extraordinarily sad".
In Washington, Secret Service spokesman Ed Donovan said that vetting for criminal history and other appropriate background checks of the people onstage were the responsibility of the South Africans. He added that Secret Service agents are "always in close proximity to the president".