A NATO soldier was among those wounded, the ministry said.
The Taliban, ousted from power after a U.S.-led military operation in 2001, has stepped up its activities over the past year, with an increase in suicide bombings and other attacks.
On November 9, one Italian soldier was killed and four others were seriously injured after a suicide bomber rammed a vehicle laden with explosives into a NATO-led convoy in the area of Shindand, south of Herat. One local resident was also injured.
On October 16, Taliban militants stopped two buses carrying 77 people in the southern Kandahar region and massacred over 30 passengers, accusing them of collaborating with the central government.