KABUL (Reuters) - Demonstrators took to Afghanistan’s streets for a third day on Sunday to protest against a U.S. preacher’s plan to burn copies of the Koran even though he has since withdrawn the threat.

Chanting “Death to America” and “Death to Christians”, demonstrators clashed with Afghan security forces in Logar province, south of the capital Kabul.

The pastor of an obscure U.S. church has abandoned plans to burn the Moslem holy book on the anniversary of the September 11 attacks on the United States. But there were at least three incidents of desecration in New York and Tennessee on Saturday.

Word of the intention to burn the Koran had already triggered outrage in Afghanistan and across the Muslim world. President Barack Obama warned it could hurt the United States deeply abroad, endanger U.S. troops in Afghanistan and risk attacks in U.S. and European cities.

Three demonstrators were wounded, one seriously, when Afghan security forces opened fire on Sunday to disperse hundreds of protesters marching to Pul-e-Alam, the capital of Logar province, said Din Mohammad Darwish, the provincial governor’s spokesman.

The protesters threatened to attack foreign military bases. There are almost 150,000 foreign troops fighting a growing Taliban-led insurgency in Afghanistan.

“The governor must give us an assurance that the church is not going to burn the Koran, otherwise we will attack foreign troop bases in our thousands,” protester Mohammad Yahya said.

Major Patrick Seiber, a spokesman for the NATO-led International Security Assistance Force in Afghanistan’s east, said ISAF was aware of more protests in Logar on Sunday but put the crowd at about 100.

Seiber said there had been reports of some injuries after rock-throwing and stick-wielding protesters clashed with Afghan security forces in Logar’s Baraki Barak district.

Afghan police and troops blocked roads to stop protesters reaching Pul-e-Alam from Baraki Barak, Darwish said.

On Saturday, four demonstrators were seriously wounded when Afghan security forces opened fire as protesters hurled stones and tried to storm government buildings in Pul-e-Alam.

On Friday, a protester was shot dead when an angry crowd attacked a German-run ISAF base in Faizabad in northeastern Badakhshan province. Protesters also gathered in Kabul and four other provinces on Friday as anger grew over Jones’s plan.

Similar protests over perceived desecration of Muslim symbols have led to dozens of deaths in Afghanistan in recent years, including after a Danish newspaper published a cartoon depicting the Prophet Mohammad in 2005.

Officials in Faizabad said the German-run base was singled out after German Chancellor Angela Merkel paid tribute to free speech at a ceremony last week for the Dane who drew the cartoon.

On Thursday, the United Nations’s top diplomat in Afghanistan said the protests risked delaying Afghanistan’s September 18 parliamentary election.

The election is seen as a key test of stability in Afghanistan before Obama conducts a strategy review of the increasingly unpopular war in December.

The Taliban were ousted by U.S.-backed Afghan forces in late 2001 for sheltering al Qaeda leaders, including Osama bin Laden.