Members of the international deaf community are expressing outrage over a fake sign language interpreter "making up his own signs" at former South African President Nelson Mandela's memorial on Tuesday, Yahoo! reports, and the fraud has now been identified.

"The structure of his hand, facial expressions and the body movements did not follow what the speaker was saying," South African and board member of the World Federation of the Deaf Youth Section, Braam Jordaan, told SBS News. "What happened at the memorial service is truly disgraceful thing to see - it should not happen at all."

Sheena Walters, a representative for the World Association of Sign Language Interpreters, echoed Jordaan's sentiments to the news organization, explaining that the interpreter was not signing any of South Africa's 11 official languages, or any recognizable one for that matter.

"Most sign languages across the world share a similar structure and pattern and this person seems to be making a lot of repetitive signs and isn't displaying the usual facial expression or structure of sign language that you would normally see," Walters explained.

The memorial, which was streamed internationally and featured a speech from U.S. President Barack Obama and attended by nearly 100 heads of states, took place in Johannesburg. South African sources have identified the interpreter as Thami Jantjie, whose abilities have apparently been questioned in the past.

"He was a complete fraud," Cara Loening, director of Sign Language Education and Development in Cape Town, told Agence France-Presse. Meanwhile, many have taken to Twitter to express their outrage.