European truce monitors in Sri Lanka say they believe the army was behind the recent killings of 17 local aid workers. They said there were signs that government forces carried out the execution-style attacks in the north-eastern town of Mutur earlier this month. The killings followed several days of fighting between Tamil Tiger rebels and government forces. The slain workers belonged to the French charity Action Against Hunger. The monitors are in Sri Lanka to oversee a fragile 2002 truce between the rebels and government forces.