At least nine people have been killed and 12 others injured in a large explosion at the entrance to a NATO base and airport in the city of Jalalabad in eastern Afghanistan, police say.
Hazrad Mohammad, provincial police spokesman, said "a very strong'' blast hit the airport in Nangarhar province on Monday morning.
A suicide bomber drove up to the gates of the airport, which primarily serves international military aircraft, and detonated his explosives shortly after daybreak, Mohammad said.
According to Reuters news agency, Afghan Taliban claimed responsibility for the attack saying it was "revenge" for the burning of copies of the Quran which sparked off deadly protests almost a week ago.
American officials have called the disposal of the books a mistake and have issued a series of apologies.
Among the dead were six civilians, two airport guards and one soldier, Mohammad said.
An Associated Press photographer at the scene saw at least four mangled, charred cars at the site destroyed in the blast.
NATO forces spokesman Captain Justin Brockhoff said that no international forces were killed in the attack and that the base was not breached by the blast, AP reported.
More than 30 people have been killed, including four US soldiers, since protests erupted over the burning of copies of the Quran in an incinerator pit at the US-run Bagram airbase north of Kabul.
"Most of the deaths have been Afghans caught up in violence at protests, or shot by security forces," Al Jazeera's Bernard Smith, reporting from Kabul, said.
"The Taliban have been encouraging people to attack foriegn troops, but its been mostly Afghan casaulties."
Al Jazeera's Alan Fisher, reporting from Washington DC, said "the Americans have been caught off-guard by what happened on Monday ... They have appealed for calm, they said they were sorry and that still hasn't quelled the protests we are seeing right across Afghanistan.
"The bomb attack on the airport in Jalalabadcertainly shook the Americans quite considerably. There was a great deal of loss of life and they will be hoping that they can quickly get this under control by speaking to the Afghans and hoping that voices of calm can prevail in the local communities".
Appeal for calm
Our correspondent said that on their part, the Afghans want the US to prosecute those who were guilty of disrespecting their holy book.
"But at the moment the Americans don't seem inclined to do that. So they are hoping that by sitting tight over the next couple of days that things will calm down," he said.
The Afghan president, Hamid Karzai, went on television on Sunday to appeal for calm.
Karzai "condemned with the strongest words" the treatment of the Quran and said the perpetrators should be punished.
At the same time, he told his countrymen: "Now that we have shown our feelings, it is time to be calm and peaceful".
He said he respected the emotions of Afghans upset by the incident, but urged them not to let "the enemies of Afghanistan misuse their feelings".
According to a Pentagon spokesperson The US military remains fully committed to its war strategy in Afghanistan and to an alliance with the Kabul government despite events in the past week.
Defense Secretary Leon Panetta and top US military officer General Martin Dempsey both "believe that the fundamentals of our strategy remain sound," spokesperson George Little told reporters.
Seven US soldiers were wounded on Sunday in a grenade attack on their base in Kunduz province, police said.
Earlier the Taliban claimed to have been behind the shooting deaths of the two US advisers in the interior ministry in Kabul on Saturday. The Taliban also said they were behind an attempt to poision the food of US soldiers in eastern Afghanistan.
Meanwhile, Afghan officials, including the defence and interior ministers, cancelled forthcoming planned visits to Washington so they could remain in Kabul for consultations about how to quell the recent violence, US officials said.