Allowing a mental-health patient with violent tendencies to stand next to the President of the United States Barack Obama at Nelson Mandela’s memorial service has been termed as a “major security lapse”.

The sign-language interpreter for Obama and other world leaders at Nelson Mandela’s memorial service, Thamsanqa Jantjie, said in interviews published that he frequently has been violent and was hospitalised in a mental health facility for over a year. He said he is officially classified as disabled by the government because of his schizophrenia. Jantjie, who has been accused of using fake signs that amounted to gibberish, said he suffered a schizophrenic episode while on stage in which he had visions of angels.

The South African Government reportedly was investigating whether the interpreter had been vetted before the memorial service.