KIRKUK - Islamic State militants killed at least 10 people including a local Sunni tribal sheik in two separate attacks late on Sunday in Iraq's northern provinces of Mosul and Kirkuk, police and local officials said.In a village near the Sunni town of Shirqat, south of Mosul, Islamists stormed the house of a tribal sheik who led a Sunni militia that had fought against the militants, killing him, his son and two guests, police sources said.Islamic State, which had seized control of much of northern Iraq in 2014, lost Shirqat to U.S.-backed Iraqi security forces supported by Sunni tribal fighters in 2016. However, a small number of militants are still operating in the area and are capable of launching sporadic attacks, security officials said.In the town of Nijana, south of the oil city of Kirkuk, five members of one family were killed by militants who set up a fake security checkpoint on a main road. The family were Shi'ite Turkmens - a father who is an Iraqi soldier, his pregnant wife, his two children and his brother-in-law.Local police said their five charred corpses were found inside the burned-out car, after the militants fled the scene. Two police officers accused Islamic State militants of carrying out the attack.Another passer-by was also killed inside his car during the attack, said police sources.