KABUL: At least six people were killed and seven wounded in a suicide car bomb attack at the gates of Jalalabad airport in eastern Afghanistan on Monday, police said.

“Six people are dead,” Nangarhar provincial police spokesman Hazrat Mohammad told AFP. Nato troops have sealed off the area, where they have a base, said provincial spokesman Ahmad Zia Abdul Zai.

The attack comes after at least 30 people were killed in six days of violent anti-US demonstrations across the country in protest over the burning of Korans at a US military airbase.

On Sunday, seven US soldiers were wounded in a grenade attack on their base in northern Kunduz province, police said.

President Hamid Karzai went on television Sunday to appeal for calm.

Karzai “condemned with the strongest words” the treatment of Islam's holy book and said the perpetrators should be punished, but 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 Koran burning in an incinerator pit at Bagram base north of Kabul, but urged them not to let “the enemies of Afghanistan misuse their feelings”.

Taliban insurgents have called on Afghans to kill foreign troops in revenge for the incident, and claimed to have been behind the shooting deaths of the two US advisers in the interior ministry in Kabul on Saturday.