Authorities say the attacker targeted a police station in the city of Khost, near the border with Pakistan.  At least two police officers and women and children were among the dead.

The Taliban claimed responsibility for the attack which was condemned by Afghan President Hamid Karzai and NATO. 

Elsewhere in the east, Afghan officials said a roadside bomb killed three Afghan police officers in Nangarhar province.

In other violence the same day, NATO says a person wearing an Afghan army uniform opened fire on NATO troops in northern Afghanistan, killing two German soldiers and wounding seven others.

The incident took place at a coalition outpost in the Pul-e-Khumri district of Baghlan province. Soldiers were working on a vehicle when they came under fire, said NATO. They returned fire, critically wounding the attacker.

Germany has around 5,000 troops stationed in northern Afghanistan. At least 47 German soldiers have been killed since the conflict began in 2001.

Also on February 18, NATO said one of its service members died following a bomb blast in southern Afghanistan, but gave no other details.

In eastern Kunar province, more than 30 insurgents were killed during an overnight operation, according to the alliance.