US spending on aid work in Afghanistan is only a fraction of what the American military spends, and too much of that aid money is for the high salaries of expatriate employees, an international aid agency said Tuesday. Meanwhile, air strikes from US-led coalition forces killed a "large group" of insurgents in southern Afghanistan early Tuesday, the coalition said in a statement. A local official said 14 militants were killed in the operation. Though the US Agency for International Development has spent more than $4.4 billion in Afghanistan since 2002, Britain-based international aid agency Oxfam said that figure is dwarfed by US military spending here - $35b. in 2007 alone. The US Embassy in Kabul said it could not immediately comment.