The chairman of the US Joint Chiefs of Staff says an investigation has so far turned up no evidence of US interrogators at Guantanamo Bay desecrating the Muslim holy book, the Quran, reports CNN.

In its latest edition, Newsweek magazine quoted sources as saying that investigators probing abuses at the military prison had found that interrogators "had placed Qurans on toilets, and in at least one case flushed a holy book down the toilet."

The report provoked public outrage in Muslim countries and violent demonstrations in Afghanistan.

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But an investigation by the US Southern Command, which has jurisdiction over the US Naval Base at Guantanamo Bay, Cuba, has so far turned up no evidence that that incident took place, said General Richard Myers.

"They have looked through the logs, interrogation logs, and they cannot confirm yet that there was ever the case of the toilet incident," he said.

Pakistan, a close ally of the United States in its war on terror, has condemned the reported incidents at Guantanamo and urged strong punishment for anyone found responsible.