Deaf people watching the Nelson Mandela memorial were bemused and shocked by a "fake" sign language interpreter on stage whose gestures were unintelligible.
The interpreter was watched by millions as he stood beside speakers at the event including President Barack Obama.
Hundreds of people took to social media to express their anger at the interpreter's gestures, and several deaf groups confirmed his signing did not reflect the comments being made to honor the anti-apartheid icon.
The signer at Mandela's memorial has drawn criticism for not actually interpreting the speeches of dignitaries for deaf people around the world. Watch and weigh in.
Paul Breckell, chief executive of the U.K.-based charity Action on Hearing Loss, said: "We are shocked by the quality of sign language interpretation at Nelson Mandela’s memorial - if it could be called interpretation at all."
He added that "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."
Among the first to express their dissatisfaction was Wilma Newhoudt-Druchen, the first deaf woman to be elected to the South African parliament, who tweeted that the signing was "rubbish," adding: "He cannot sign. Please get him off." She took to the social media site several times during the day.
David Buxton, chief executive of the British Deaf Association, said in an email that "the gentleman is a total fake." "He has no real clue about sign language and has obviously upset the deaf community of South Africa as we have received hundreds of angry messages via Facebook and Twitter," said Buxton, who was watching the ceremony with his South African-born wife.
Buxton called on the South African authorities to "name and shame that gentleman." He said the same interpreter had provided sign language for South African President Jacob Zuma’s speech at a military event last year.
The South African government said in a statement that it was "looking into this matter but has not been able to conclude this inquiry due to the demanding schedule" organizing the state funeral.
Dozens of world leaders from President Obama to UN chief Ban Ki-Moon lauded the late "giant of history" at a memorial service Tuesday, as tens of thousands cheered from the sidelines.
Braam Jordaan, a profoundly deaf South African citizen and board member of the World Federation of the Deaf Youth Section, explained why it had been so clear to sign language users that the interpretation was not correct. He told NBC News in an email: "The structure of his hand, facial expressions and the body movements did not follow what the speaker was saying."
South African sign language interpreter Francois Deysel tweeted during the ceremony that the interpreter was "making a mockery of our profession."