A suicide attacker drove an explosives-laden vehicle into an Afghan army bus in the western city of Herat on Tuesday, wounding 12 people, police and the army said.
The attacker struck the bus near the airport on the outskirts of the city as civilians were trying to enter the complex and the army vehicle was passing by, the defence ministry and Herat police chief Mohammad Shafiq Fazli said.
"Ten soldiers and two civilians were wounded in the suicide attack," a defence ministry statement said.
Blood, body parts and the car used for the suicide attack were scattered across the area, an agency reporter at the scene said.
Afghan soldiers and police and NATO-led forces cordoned off the site.
The blast gouged a crater into the tarmac and damaged the bus.
Suicide attacks are a key feature of an insurgency launched by the Taliban movement after it was driven from government in late 2001 by a US-led coalition.
Last year they spiked from 27 to nearly 139, according to the US military.
The defence ministry reported meanwhile that its troops had killed two "enemy" in southern Zabul province on Monday and seized weapons and motorbikes "used for terrorist activities."
Commanders of the nearly 40,000 foreign troops trying to help the government gain control of the country have warned of more suicide attacks this year as they are easier for the rebels than confronting troops in conventional battle.