KABUL (July 6, 2009)--Officials say a seventh American has been killed in violence Monday in Afghanistan.

A U.S. military spokesman says the soldier died of wounds sustained during a firefight with militants in the east of the country.

Four U.S. soldiers died when their vehicles struck a roadside bomb in a province in the north.

In the south, another explosion killed two more American troops.

The seven American deaths come as thousands of U.S. Marines continue their major offensive against the Taliban in Helmand province, a southern militant stronghold.

It is the biggest U.S. military operation since the ouster of the Taliban from power in
2001.

A suicide car bomber also blew himself up outside the gate of the main NATO base in the region, killing two civilians and wounding 14 other people.

Also today, the Taliban confirmed it’s holding an American soldier captive.

The U.S. military had said that a soldier was discovered missing last week.

The soldier was described as possibly being in enemy hands.

Details of such incidents are routinely held tightly by the military, as it works to retrieve a missing or captured soldier without giving away any information to captors.