Four booby-trapped vehicles have been detonated in Iraq, killing at least 41 people, and injuring 150. Two car-bombs exploded in the capital Baghdad. They were aimed at building sites in predominantly shi-ite south-western districts of the city. 16 casual labourers who were waiting for work were killed.One eyewitness said: “A bomb was hidden in a cement bag in the streets of the Amil area where workers had gathered.” Another witness said: “People were gathering here to earn their living. What did they do to deserve this? How can God accept it?” 400 kilometres north, in a predominantly shi-ite village near Mosul, two truck-bombs killed 25 people and injured 75. Around 30 homes were razed to the ground. The insurgency in Iraq had weakened in the past 18 months, but several big attacks since US troops withdrew from urban areas have raised doubts about Iraqi forces’ ability to cope on their own.