A key Taliban commander was killed by joint forces in the massive NATO-Afghan operation to take the control of Taliban bastion in southern Afghanistan, spokesman for provincial administration Daud Ahmadi said Saturday.

"The joint forces during cleanup mission in Marja district (of Afghanistan's southern Helmand province) on Friday killed commander Mullah Amanullah," Ahmadi told Xinhua.

However, he failed to give the exact number of Taliban fighters who might have been killed or wounded along with commander Amanullah.

Days ago, the governor of Helmand province Gulab Mangal confirmed the dead of over 40 militants during the operation.

So far 11 NATO-led peacekeeping forces and an Afghan soldier have been killed in roadside bombs and gunshots related to the Operation "Moshtarak" or Together in Marja, which was launched last Saturday, according to media reports.

Taliban militants, who staged a bloody comeback four years ago, have yet to make comments over claim on Amanullah's elimination.

The operation Moshtarak 13 with the involvement of nearly 15, 000 Afghan and NATO troops as well as U.S. Marines covering Marja and neighboring Nad Ali districts with objective to restore government control and lasting peace in the troubled region.