Religious tension overshadowed Saturday's anniversary of the September 11 attacks on the United States where President Barack Obama urged a Christian preacher to abandon a plan to burn copies of the Koran.
News of the planned burning has outraged Muslims around the world. In Afghanistan, protestors clashed with security forces, as thousands of Afghans demonstrated for a second day.
And a day ahead of the ninth anniversary, a report warned that the United States faced a growing threat from home-grown insurgents and an "Americanization" of the al Qaeda leadership.
On Friday, Obama appealed to Americans to respect the "inalienable" right of religious freedom and said he hoped the preacher would abandon his plan to burn the Muslim holy book, saying it could deeply hurt the United States abroad.
"This is a way of endangering our troops, our sons and daughters ... you don't play games with that," Obama told a Washington news conference in which he included an appeal for religious tolerance.
Pastor Terry Jones, of the obscure Dove World Outreach Centre in Gainesville, Florida, has backed off a threat to burn the Koran on the anniversary of the Sept 11, 2001 attacks in which nearly 3,000 people died.
Jones arrived late on Friday in New York, where he was scheduled to appear on NBC's "Today" show on Saturday morning.
He had said he would call off the Koran burning if he could meet with Muslim leaders seeking to build an Islamic centre and mosque near the Manhattan site of the Sept 11 attacks with the aim of getting it relocated.
While the bewhiskered fundamentalist preacher kept people guessing about his precise intentions, an evangelist acting as a spokesperson, KA Paul, said he could "guarantee" Jones would not go ahead with the event.
Referring to "the individual down in Florida," Obama noted the pastor's Koran-burning plan had already caused anti-American riots in Afghanistan, where US troops are in a gruelling war against Muslim Taliban militants.
Several thousand people gathered in three districts in Afghanistan's northeastern Badakhshan province, where a day earlier a protester was shot dead outside a German-run NATO base, provincial police chief Aqa Noor Kentuz said.
