Kabul, Afghanistan ? U.S. soldiers and warplanes drove off an insurgent attack on a new American base early Wednesday, reportedly killing 19 militants in an area where rebels are trying to resist a push by coalition troops into remote mountains of eastern Afghanistan.

In the volatile south of the country, racked by the bloodiest fighting in nearly five years, suspected Taliban rebels hanged a 70-year-old woman and her son from a tree, accusing them of spying for President Hamid Karzai’s government, officials said.

Meanwhile, Karzai, whose popularity has declined because of slow progress in reconstructing the war-battered country and poor security, signaled in an interview that he won’t run for president again in elections slated for 2009.

The raid on the U.S. base at Kamdesh in the eastern province of Nuristan – one of the country’s wildest regions – was staged by extremists likely belonging to the Hezb-e-Islami militant group, who attacked from three directions out of forests using rocket-propelled grenades and small-arms fire, the U.S. military said.

Several hundred soldiers at the base, which lies in a small town but backs onto a sheer mountain face, returned fire with mortars and small arms before jets dropped four 500-pound bombs, ending the clash that lasted more than two hours.