Suicide attackers stormed government buildings in the Kurdish-controlled city of Kirkuk in north of Iraq and killed 16 at a construction site as the troops advanced to Mosul. <br/><br/>The local mayor said that in one incident, three bombers infiltrated a power plant being built by an Iranian company near Dibis, a town about 40 kilometres northwest of Kirkuk.<br/><br/>The mayor said the attack led to clashes with security forces, who managed to kill one of the bombers before he detonated his vest. He said that the other two blew themselves up once they were surrounded.<br/><br/>There was no immediate claim for the attacks but nearly all such raids have been carried out by the Islamic State group, which is attempting to defend its last major Iraqi stronghold against a massive military offensive.<br/>