Bomb kills 6 in Iraq during UN chief's visit

BAGHDAD (AP) — Iraqi officials say a car bomb exploded on a commercial street in northern Baghdad, killing at least six people.

Monday's attack comes as the visiting U.N. chief Ban Ki-moon called on Iraq's leaders to "address the root causes" of a surge in bloodshed as al-Qaida militants battle government forces and allied tribal leaders for control of a volatile mainly Sunni province west of the capital.

Police and hospital officials, speaking on condition of anonymity because they weren't authorized to release the information, said those killed were civilians and 13 people also were wounded.

Violence has surged as extremist militants have tried to position themselves as the champions of Iraqi Sunnis angry at the Shiite-led government over what they see as efforts to marginalize them.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

The U.N. chief has arrived in Baghdad as an unprecedented standoff is underway between Iraqi troops and al-Qaida-linked militants in western Anbar province.

Ahead of Ban Ki-moon's visit on Monday, the Iraqi government said the U.N. secretary-general would discuss a number of "regional issues, especially the crisis in Syria" next door.

Iraqi security forces and allied Sunni tribesmen in Anbar have been battling al-Qaida fighters from the Islamic State in Iraq and the Levant but have yet to recapture the city of Fallujah and also part of the provincial capital, Ramadi.

The extremist militants, emboldened by fellow fighters' gains in the war in neighboring Syria, have tried to position themselves as the champions of Iraqi Sunnis angry at the Shiite-led government over what they see as efforts to marginalize them.