Former Iraqi athletes trying to prove that Saddam Hussein's son Uday had sports stars tortured and killed for losing said on Wednesday they feared the evidence had gone up in smoke in a U.S. air strike on the headquarters of Iraq's National Olympic Committee.

"I'm not worried about the concrete or the furniture but I am worried about the evidence," said Issam Thamer al-Diwan, a former volleyball player and coach who alleges 52 athletes were murdered on the orders of Uday and others in the Hussein clan.

"I want to show that to the world, to show how they used the logo of the International Olympic Committee to cover up their crimes," Diwan said by telephone from the San Diego area of California where he has lived since fleeing Iraq in 1991.

Several exiled Iraqi athletes have made torture allegations. Iraq denies rights abuses and Jorge Vieira, a Brazilian who coached Iraq's soccer team in the mid-1980s, told Reuters last week he had no knowledge to support the claims.

Diwan said Uday, 39, had him thrown in jail for three months in September 1990 after he refused to go with other sports officials to Kuwait to loot sports equipment following the Iraqi invasion.

"They tied my hands behind my back and made me stand upright in an uncomfortable position for three days," Diwan, 45, said. "I told them I had a sports injury in my left knee so they kicked me there," he said.

The seven-story headquarters of the National Olympic Committee, headed by Uday, was hit from the air late on Monday in the U.S.-led war on Iraq and remained burning for hours.

Diwan, 45, said the basement and first floor housed cells where Uday would have sports players humiliated and beaten if they failed to win.

Offices of the Fedayeen, one of the irregular militias resisting U.S. and British troops, were also on the first floor, while Uday had his offices on the fourth and used the top floor for private parties, Diwan said.

'HE'D HIT THE ROOF'

Another exile, former national soccer team captain Abed Kadhim, said athletes and sports journalists would also be taken to Baghdad's al-Radwaniyah prison to be tortured.

"I was not present when they were taken there, but I know they were subjected to torture and I know the practice was widespread," said Kadhim, 61, who also coached the soccer team in Uday's Al-Rashid sports club.

"I'm worried that some of the documents proving this will be lost now, but the most important thing is that a lot of the people who were tortured by Uday are still around," he said.

He said Uday, who also heads the Iraqi soccer federation, sometimes would have the head of every player in the national team forcibly shaved, in a sign of humiliation, if they lost.

"He has a quick temper," Kadhim, who left Iraq in 1994, said of Uday. "You'd see him laughing his head off for no reason, then all of a sudden he would hit the roof."

As Saddam's elder son, Uday was regarded as the Iraqi president's heir apparent until he was wounded in a gun attack in 1996.

His father put him in charge of the Olympic Committee and the soccer federation in 1984, midway through the war with Iran, to secure sporting success as a way to boost morale.

Diwan said he had been with the volleyball team in Kuwait as an assistant coach in 1987 for Iraq's first sporting clash with Iran since the outbreak of the war in 1980.

"Uday called from Baghdad and said 'If you lose the match, we'll lose the war, so don't come back to Iraq'," Diwan said. "We won 3-1. We wanted to save our necks."