Former prisoners at Guantanamo Bay have charged in the past that US interrogators defiled the Quran, and a freed detainee said this week that Islam's holy book was desecrated at the main US military base in Afghanistan.

As Afghan towns calm after riots that killed at least 15 people, questions remain over why Newsweek's since-retracted 200-word report that Guantanamo interrogators put a Quran in a toilet triggered such a violent response, when similar claims over the past year did not.

Afghan students step up protests

Yesterday, Afghan President Hamid Karzai's spokesman charged that "elements from within and outside Afghanistan" manipulated peaceful protests into violence, seeking to spread unrest while Karzai was in Europe -- and ahead of his trip to Washington to discuss a long-term strategic relationship.

Afghans' strong feelings about the Guantanamo prison camp in Cuba gave an opportunity for "enemies of Afghanistan and for those who are keen to cause destruction in Afghanistan" to instigate riots, spokesman Jawed Ludin told reporters.

Newsweek retraction not enough: US

Ludin did not name anyone specifically, but it was likely that he was alluding to neighboring Pakistan. Indignation over the Newsweek story first surfaced in Pakistan at a news conference by Imran Khan [Images], a former captain of his country's cricket team but now a member of Pakistan's lower house of Parliament and a leading critic of the U.S.-led war on terrorism. Taliban and al-Qaida loyalists also have found refuge among Islamic hard-liners in Pakistan.

Newsweek's apology and retraction of its story Monday was welcomed by the Afghan government but shunned in neighboring Pakistan, where Islamic fundamentalists said they would press ahead with plans for mass protests.

Pakistani Information Minister Sheikh Rashid Ahmed said the report "insulted the feelings of Muslims. ... Just an apology is not enough."

No Quran abuse, says US

Gen. Richard Myers, chairman of the Joint Chiefs of Staff, said at the Pentagon last week that the U.S. commander in Afghanistan, Gen. Carl Eichenberry, doubted whether the Newsweek report was behind the Afghan violence.

Eichenberry thought the rioting was "more tied up in the political process and the reconciliation process that President Karzai and his Cabinet is conducting in Afghanistan," Myers said. "He thought it was not at all tied to the article in the magazine."

But Col. Gary Cheek, commander of U.S. forces in eastern Afghanistan, said Monday that he knew of no evidence that militant supporters of Afghanistan's former Taliban regime provoked the trouble, and he stressed the need for the US military to engage more with Muslim leaders.

Regardless of explanations into what fanned the violence, it's clear that sensitivity over treatment of the Quran is a raw nerve in deeply conservative and poor Afghan communities.

The furore caused by the Newsweek report -- prompting protests and angry words from Muslim leaders in many countries -- appeared to embolden former inmates of Guantanamo staying in Pakistan to air more accusations that US personnel abused the Quran.

Abdul Rahim Muslim Dost, a 42-year-old Afghan freed from Guantanamo last month, on Monday told the Pakistani network Khyber TV that an Arab inmate had recounted to him and others in the prison how interrogators threw a Quran to the floor and stepped on it.

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