Afghan Soldier Kills 2 US Troops

Two American troops were killed when a rogue Afghan soldier opened fire Monday morning, the latest in a series of so-called "insider attacks" that have severely damaged the trust between coalition forces and their Afghan allies.

Monday's attack happened in Laghman province, in a river valley rife with Taliban activity. It's the same area where an ABC News crew was caught in a Taliban ambush in July.

According to NATO officials, the U.S. soldiers were part of a wheeled convoy travelling through the Alingar valley when one of their vehicles was hit by a roadside bomb. When the soldiers dismounted to investigate, there was an altercation between them and an Afghan soldier. The Afghan soldier then pulled his weapon and fired, killing two U.S. soldiers before he was killed by return gunfire.

Gunman Kills 3 Marines in Afghanistan Watch Video

Senior U.S. Soldier Killed in Afghanistan Watch Video

Tropical Storm Isaac Slams Haiti Watch Video

With today's attacks, 12 American soldiers have been killed in the last month, all at the hands of their Afghan allies. This year, 42 coalition troops have been killed in insider attacks. The majority of them were American. The total surpasses the entire amount of insider attacks in 2011, when 35 coalition troops were killed by Afghan allies.

In response to this year's rash of attacks, the top U.S. general in Afghanistan, Gen. John Allen, has ordered all troops to carry armed weapons with them at all times – on base and off. Afghan officials have also promised to review their recruitment process, which has come under criticism for not vetting candidates properly before allowing them to enlist in Afghanistan's armed forces.

Elsewhere in the country, Afghan officials discovered 17 bodies – all of them beheaded – abandoned at roadside in Southern Afghanistan. The civilians were executed by the Taliban after attending a mixed-gender party where there was music and dancing, according to Mullah Sharafuddin, the governor of Kajaki district in Helmand province, where the bodies were found.

During Taliban rule, most types of music were made illegal, and anyone caught attending a mixed-gender party faced stiff punishment, including death in the most extreme cases.