Afghanistan's defense minister, who played a key role overseeing the rapid expansion of the country's army, stepped down on Tuesday days after receiving a no-confidence vote from parliament.

The resignation of Abdul Rahim Wardak, one of the members of President Hamid Karzai's cabinet who was trusted by Washington, leaves his key ministry without its longstanding leader at a time when Afghan troops are charged with taking over responsibility from international forces by the end of 2014.

Separately, a truck bomb rammed into the gate of a NATO base in eastern Afghanistan, seriously wounding several people, while a roadside explosion killed nine civilians riding in a bus near the Afghan capital. NATO also reported that three service members were killed during the past two days as fighting continued in the east and south where militants have their deepest roots.

Lawmakers last Saturday passed