A U.S.-backed military offensive against Islamic State fighters faltered in its first week as several hundred militants entrenched in the provincial capital of Ramadi withstood punishing airstrikes and held off a far-larger force of Iraqi ground troops, senior U.S. and coalition commanders said Saturday.
The slow going in what officials portray as a major test of efforts to bring Iraq's fractured security forces into a common front against the Sunni Muslim extremists comes as a truck bomb late Friday killed more than 100 people, including women and children, in a mostly Shiite Muslim market town about 35 miles north of Baghdad.