Prince Ali bin al Hussein, who is challenging Sepp Blatter for FIFA's leadership, said Wednesday that the arrest of six football officials in a US corruption probe was "a sad day" for the sport.
But the prince did not use the arrests to launch a new attack on Blatter, who he has accused of tarnishing the image of football's world body which has been tainted by repeating scandals.
"Today is a sad day for football," the Jordanian prince, a FIFA vice president, said in a statement.
"Clearly this is a developing story, the details of which are emerging. It would not be appropriate to comment further at this time," he added.
The arrest of six football officials in Zurich, who could be extradited to the United States, came just two days before a vote for FIFA's president. Blatter is favourite to secure a fifth term.