The Confederation of African Football has told the Benin coach Reinhard Fabisch he has 24 hours to sign an affidavit confirming his allegation of a bribery attempt at the African Nations Cup finals.
CAF yesterday drafted a letter to the Benin Football Federation seeking clarity over allegations Fabisch made that he was asked to help fix the result of his side's opening Group B match which they lost 1-0 to Mali in Sekondi on Monday.
The CAF secretary general Mustapha Fahmy said they were investigating and their disciplinary committee chairman Raymond Hack said the matter was being seriously considered.
"A letter has been sent and we wait to get formal confirmation of the allegation before we take the matter further," he added.
On Thursday, Fabisch said that he had been approached by a man who claimed to be from a Singapore-based company.
"He wanted to find out from me if there was any possibility of manipulating the match," Fabisch told the BBC.
The German coach, who previously worked in Zimbabwe, South Africa and Kenya, said he had told the unidentified man he had two minutes to leave or the police would be called.
Fabisch said he received the approach at the team's hotel on Saturday, two days before the Mali defeat.
The man said the company he represented claimed to be able to fix matches across Africa and planned to win money in bets on the tournament's opening goal.
"I was astonished that he had the guts to approach a German to fix a football match," Fabisch said.
"I think that African players are vulnerable to this kind of approach, because many of them don't have money. This is why poor countries like Benin are targeted."
CAF officials said they were concerned that no formal notification of the approach had been given to them before Fabisch spoke to reporters.
They added that if Fabisch did not sign an affidavit confirming the allegation then CAF would consider charging the Benin federation with bringing the game into disrepute.
CAF said the federation was responsible for the actions of its officials, including the coach. Benin lost 4-1 to Ivory Coast yesterday evening in their second Group B match, while Nigeria were due to play Mali in last night's late match in Sekondi.
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