Thousands of Afghans demonstrated Thursday north of the capital Kabul by throwing rocks at Afghan police and a US military convoy to protest a US church's plan to burn copies of the Quran.

The enraged protesters planned to march from Mahmoud Raqi, capital of Kapisa province, to Bagram airfield, the main US military base in Afghanistan, but were stopped by Afghan police, Abdul Halim Ayar, spokesman for the provincial governor, said.

A police officer was injured when angry youths overran the police barricades and threw stones at Afghan forces and a three-vehicle US military convoy, Zohor Kohistani, one of the protesters, told DPA.

Both Afghan forces and US military personnel fired in the air to disperse the mob and open the way for the convoy to pass, he said.

'The men were shouting 'death to America' and 'death to the US church' that plans to burn our holy book,' he said.

Ayar said that 10,000 people took part in the five-hour demonstration, while Kohistani put the number at around 3,000.

Another protest was also reported Thursday on the eastern outskirts of Kabul, where demonstrators burned effigies and threw rocks at Afghan police who were trying to control the mob.

An evangelical Christian congregation of only 50 members the US state of Florida plans the book burnings to mark Saturday's ninth anniversary of the Sep 11 attacks on New York and Washington.

The plan has sparked widespread international condemnation.

Siamak Herawi, spokesman for President Hamid Karzai, said Thursday that Kabul 'strongly condemns the plan' and has asked US authorities to prevent the church from its 'disrespectful' action.

Staffan de Mistura, the UN secretary-general's envoy to the country, said that the plan would put in jeopardy the efforts of Afghans and foreigners working to bring peace in Afghanistan.

Aid agencies in Afghanistan have also said that the plan could cost the lives of innocent civilians and aid workers in the country.

The top commander of NATO forces in Afghanistan, US General David Petraeus, also criticised the church and said the Taliban could use the act to inspire its fight against foreign troops.