Afghan soldier shot and wounded five U.S. soldiers

An Afghan soldier shot and wounded five U.S. soldiers late Tuesday at a base in eastern Afghanistan in what is the latest in a series of "green on blue" attacks by local forces on their coalition counterparts.

Tuesday's attack comes after three British troops were shot dead Sunday in southern Helmand province by a man wearing an Afghan police uniform. Afghan security forces will be responsible for defending their country when coalition troops withdraw by the end of 2014, and the incidents raise questions about their reliability.

A spokesman for the International Security Assistance Force, as the coalition is formally known, said Tuesday's attack occurred in the evening at a joint Afghan army-coalition base in the Sayed Abad district of Wardak province.