At least four U.S. troops have died in two separate attacks in Afghanistan. One servicemember was killed and three others were wounded when an Afghan soldier opened fire in southern Kandahar. It was the latest in a string of attacks against NATO occupation forces by members of the Afghan army. Meanwhile, another three U.S. soldiers were killed in a bombing in an eastern province. In a separate incident, three Afghan women were killed in the crossfire of fighting between NATO soldiers and Taliban fighters. It’s unclear who fired the fatal shots.