Iraqi military forces reached the center of the northern city of Baiji on Sunday in an effort to break an Islamic State siege of the country’s biggest refinery, triggering fierce clashes with the militants, according to an army colonel and a witness.

Separately, contradictory reports emerged over the fate of Islamic State leader Abu Bakr al-Baghdadi after U.S.-led air strikes against the group in at least two locations in Iraq on Friday night.

The United States said it had no information to indicate Baghdadi had been hit. State television cited reports that Baghdadi had been wounded. It gave no further details. […]