The Egyptian, who has been President of the IHF since 2000, is facing the allegations in a scandal over television contracts.

Prosecutors in Hamburg confirmed they suspect Moustafa improperly received €602,000 (£515,000/$830,000) in consulting fees in 2007.

Moustafa's home in Rheinfelden, Switzerland, and IHF offices in nearby Basel were raided last week by Swiss authorities following a German request.

Prosecutor spokesman Wilhelm Moellers says documents were seized in Switzerland and Hamburg.

Sports marketing agency Sportfive, which bought rights to IHF competitions from 2006 until 2009 - for a reported CH30 million (£21 million/$33 million/€24 million) - also confirmed that its Hamburg office was visited but claimed "the investigation is aimed neither at Sportfive nor at employees of Sportfive".

Handball, while little known in Britain, achieved the third highest television viewing figures for the Beijing Olympics, where France won the men's tournament and Norway the women's, and is played by 20 million people worldwide.

It is tipped by many to be the surprise hit of London 2012. 

The allegations first surfaced in January 2010 when German magazine Der Speigel claimed that the money that Moustafa received was actually paid to him in gesture of the television rights, which Sportfive had acquired for the IHF competitions.

While investigating into the report of corruption involving Moustafa, it has also allegedly been uncovered that in April 2007, Moustafa received a check for €306,000 (£262,000/$414,000) and in November 2007, money had transferred in his bank account amounting to €308,000 (£263,000/$416,000).

When quesitoned by Swiss newspaper Neue Zuercher Zeitung last year about the allegations, International Olympic Committee (IOC) President Jacques Rogge claimed that if Moustafa had been a member of his organisation he "would not tolerate such a behaviour".

At the conclusion of Sportfive's contract a new deal was signed with another German marketing company, UFA, for a reported CH60 million (£41 million/$65 million/€48 million).

Both deals were negotiated with Robert Mueller von Vultejus, who worked for Sportfive before leaving to join UFA.  

Moustafa, 67, is the first Egyptian to lead an international federation.

He was the secretary general of the Egyptian Olympic Committee between 1992 and 2000.

The IHF have refused to comment on the allegations.

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