A new Harvard study shines a spotlight:
For every 10 percent increase in the amount of food aid delivered, they discovered, the likelihood of violent civil conflict rises by 1.14 percentage points. The results confirm anecdotal reports that food aid during conflicts is often stolen by armed groups, essentially making international donors part of the rebel logistics effort. According to some estimates, as much as 80 percent of the food aid shipments to Somalia in the early 1990s was looted or stolen.
More recently, in Afghanistan, "up to one-third of the aid to Uruzgan province has reportedly fallen into Taliban hands."