Zurich - Key witnesses have "hampered" FIFA's inquiry into Germany's bid to host the 2006 World Cup by refusing to give evidence, football's world governing body said Friday.
FIFA said it welcomed a German inquiry into the German campaign which said it could not rule out that FIFA votes were bought.
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"However, many questions still remain to be answered. FIFA's investigation has been hampered by the fact that key witnesses were not willing to answer questions or provide documents," said a FIFA statement, which did not give names.
FIFA said it was still cooperating with German and Swiss authorities in their investigations into various World Cup bids.