Mandela Memorial: Deaf Signer Was 'Fake' South Africa's deaf federation has claimed that an interpreter using sign language during the Mandela memorial was a "fake." Concerns over the male interpreter had been raised by deaf people watching the service at Johannesburg's FNB Stadium on Tuesday. Bruno Druchen, national director of the Deaf Federation of South Africa, said the unidentified man, who was on stage alongside world leaders including US President Barack Obama, "was moving his hands around but there was no meaning in what he used his hands for." Sign language experts have said there was no meaning to the man's gestures South African parliament member Wilma Newhoudt, a member of the ruling party, also said the man communicated nothing with his hand and arm movements. Both Mr Druchen and Ms Newhoudt are deaf. The revelation also raises concerns over security for world leaders Three sign language experts said the man was not signing in South African or American sign languages. South African sign language covers all of the country's 11 official languages, according to the federation. Nicole Du Toit, an official sign language interpreter who also watched the broadcast, said the man on stage was an "embarrassment." The man has not been identified She said: "It was horrible, an absolute circus, really really bad. Only he can understand those gestures. Delphin Hlungwane, an official South African sign language interpreter with DeafSA, said authorities were trying to track the man down. The man also failed to indicate that the crowd was booing Jacob Zuma She said: "There was zero percent accuracy. He couldn't even get the basics right. He couldn't even say thank you. You're supposed to indicate with your facial expressions, even if it's not an exact sign. He didn't indicate that (booing of Jacob Zuma) at all. It just passed him by. Nobody knows who he is. Even at this hour we still don't have his name. Paul Breckell, chief executive of Action on Hearing Loss, said: "The use of appropriately qualified communication support is crucial to ensure that deaf people can engage with and access the same opportunities as hearing people. Sign Language, be it British, International or South African, is a visual and expressive language yet the limited number of signs, the amount of repetition, lack of facial expressions and huge gaps in translation meant that deaf or hard of hearing people across the world were completely excluded from one of the biggest events in recent history. The memorial was also affected by faulty public transport which prevented some mourners from getting to the event and a faulty audio system that prevented some of the crowd from hearing leaders' speeches.