Thousands of Afghans were protesting today over suspended plans by a small American church to burn the Koran.
At least 11 people were injured, officials said.
In the northern province of Badakhshan several hundred demonstrators ran toward a Nato compound where four attackers and five police were injured in clashes.
Protesters burned an American flag at a mosque after Friday prayers.
Two people were injured in a protest at another mosque in Farah province in the west, police said.
Pastor Terry Jones from the Dove Outreach Centre in Florida triggered outrage by announcing he would burn the Koran on the anniversary of the September 11 attacks.
He later backed off his threat after he said he was promised that a planned Islamic centre and mosque would be moved away from New York's ground zero.
Muslim leaders denied there was such a deal.
Later outside his church he said the imam he thought he made the deal with "lied to us" about moving the mosque.
Mr Jones and Imam Muhammad Musri stood side by side in a news conference where the pastor said he would cancel tomorrow's event.
Mr Musri later said there was only an agreement for him and Mr Jones to travel to New York and meet tomorrow with the imam overseeing plans to build a mosque near ground zero.
In New York, the Islamic centre project leader, Imam Feisal Abdul Rauf, said he was glad Jones had backed down but that he had not spoken to the pastor or Musri.
"We are not going to toy with our religion or any other. Nor are we going to barter," Rauf said. "We are here to extend our hands to build peace and harmony."
Many in Asia greeted the news not to burn the Koran with relief, though some said the damage already has been done.
Cleric Rusli Hasbi told worshippers attending Friday morning prayers in Indonesia, the world's most populous Muslim country, that Jones had already "hurt the heart of the Muslim world".
"If he'd gone through with it, it would have been tantamount to war," the cleric said. "A war that would have rallied Muslims all over the world."
In the Gaza Strip, Hamas Prime Minister Ismail Haniyeh told tens of thousands of Muslim faithful that they had come "to respond to this criminal, this liar, this crazy priest who reflects a crazy Western attitude toward Islam and the Muslim nation."
In Afghanistan, President Hamid Karzai said he heard Jones had perhaps abandoned his plan.
"Humiliation of the holy book represents the humiliation of our people. I hope that this decision will be stopped and should never have been considered. I ask the world for peace and stability and the respect of each other," he said.