Six US troops were killed in a helicopter crash in southern Afghanistan this week. It\'s the deadliest day for US troops since a helicopter crash in 2012. The crash is under investigation, but in a statement , the NATO coalition said there was no enemy activity at the time of the crash. The deadly crash comes as casualties in the war have dropped to some of their lowest levels in years. The latest total of US troop deaths according to USA Today is at 119 this year--down from 294 the year before. Critics say leaders in both countries are at fault. Helicopter crashes have have caused some of the largest U.S. death tolls in Afghanistan. Show Less >>