A car bomb has killed at least seven people and injured nine other people in the southern Afghan city of Kandahar.
The attack was in the parking area of Kandahar's city police headquarters.
The Interior Ministry said the dead included three police officers and four civilians.
Four police cars were destroyed and several buildings were damaged, along with several nearby market stalls.
Meanwhile, a U.S. soldier has shot and killed an Afghan guard at a base in the country's north.
Afghan officials say the shooting was the result of a misunderstanding.
They say the two had argued at the gate of the base in Sari Pul Province and the U.S. soldier fired when he feared the Afghan guard was getting ready to do the same.
The U.S. military said it was aware of the altercation and is investigating.
The shooting comes amid a wave of killings of foreign troops in Afghanistan by Afghan soldiers or by gunmen wearing the uniform of the Afghan National Army.
Compiled from agency reports