Six civilians, an Afghan soldier and two local guards were killed in the bomb attack, which comes on the seventh day of violence after the burning of the Koran at a US airbase.
Taliban insurgents have said it was revenge for the Koran burning, and they have called on Afghans to kill foreign troops in revenge for the incident.
They also claim to have been behind the killing of the two US advisers in the interior ministry.
“The foreign forces have insulted our religion and this attack was revenge”, said Taliban spokesman Zabihullah Mujahid told.
The burning, which the US says was unintentional, has sparked violent protests across the country.
US Secretary of State Hillary Clinton said that the deadly protests over the burning of Korans by US soldiers “must stop”.
“We deeply regret the incident that has led to this protest, but we also believe that violence must stop and the hard work for building a more peaceful and secure Afghanistan must continue”, she told a news conference.