A suicide bomber apparently targeting a senior security official blew himself up inside a funeral tent, killing 18 people in the latest of a series of deadly attacks chipping away at the notion of a calmer Iraq. The US military has repeatedly warned that the fight against insurgents is not over, and the bombing Monday in a village north of Baghdad was the third in as many days in Sunni Arab areas thought to have been largely rid of al-Qaida militants. There was no claim of responsibility for Monday's bombing in Hajaj, a village about midway along the nearly 30 kilometers between Saddam Hussein's hometown of Tikrit and the oil hub of Beiji, 250 kilometers north of Baghdad. But police said it bore the hallmarks of al-Qaida. Witnesses said about 70 people were inside the tent when the attacker set off his explosives soon after entering.