Security agents have destroyed the shoes thrown at US President George W Bush by an Iraqi journalist, during checks to ensure they did not contain explosives, the investigating judge says.

"The shoes were examined by the Iraqi and American security services and then destroyed," the judge said.

Journalist Muntadar al-Zaidi, 29, has been in custody in Baghdad since Sunday's dramatic shoe protest against Mr Bush, which made him an instant sensation in the Arab world.

But the judge said the lack of the key piece of evidence in the case would not prevent the investigation from proceeding.

"I would have preferred to have had the shoes as evidence for the case but since Muntadar al-Zaidi has confessed to his action and that the television pictures confirm it, the investigation can continue," he said.

Mr Zaidi's brother has said he was hospitalised after being beaten by security guards and was suffering a broken arm and ribs, as well as injuries to an eye and a leg. There were no details on his condition on Thursday (local time).

In Bethlehem, about 50 Palestinian journalists staged a bare-footed protest to show solidarity with Mr Zaidi, who relatives and colleagues said had hurled the shoes because he detested Americans and Mr Bush.

The sit-in came as hundreds of pilgrims gathered ahead of Christmas celebrations in the city where Christians believe Jesus was born.

- AFP