BAGHDAD (AP) -- The al-Qaida-inspired group that led the charge in capturing two key Sunni-dominated cities in Iraq this week vowed on Thursday to march on to Baghdad, raising fears about the Shiite-led government's ability to slow the assault following the insurgents' lightning gains.
Fighters from the militant group known as the Islamic State of Iraq and the Levant took Saddam Hussein's hometown of Tikrit on Wednesday as soldiers and security forces abandoned their posts and yielded ground once controlled by U.S. troops.
That seizure followed the capture of much of Mosul, Iraq's second-largest city, the previous day. The group and its allies among local tribesmen also hold the city of Fallujah and other pockets of the Sunni-dominated Anbar province to the west of Baghdad.
The Iraqi military also abandoned some posts in the ethnically mixed flashpoint city of Kirkuk that are now being held by the Kurdish security forces known as peshmerga, Brig. Halogard Hikmat, a senior peshmerga official told the Associated Press.
He said the Kurds moved Thursday to protect an air base and other sites, but denied reports that the whole city was under peshmerga control.
"We decided to move on and control the air base and some positions near it because we do not want these places with the weapons inside them to fall into the hands of the insurgents," said Hikmat. Iraqi government officials could not be reached to confirm the account.
Also Thursday, militants attacked an Iraqi security checkpoint in the town of Tarmiyah, 50 kilometers (31 miles) north of Baghdad, killing five troops and wounding nine, said officials, speaking on condition of anonymity because they were not authorized to talk to the media.
A spokesman for the Islamic State said the group has old scores to settle with Prime Minister Nouri al-Maliki's government in Baghdad. The Iraqi leader, a Shiite, is trying to hold onto power after indecisive elections in April.
Al-Maliki has asked parliament to declare a state of emergency that would give him the "necessary powers" to run the country -- something legal experts said could include powers to impose curfews, restrict public movements and censor the media. Lawmakers are expected to consider that request later today.
Hundreds of young men crowded in front of the main army recruiting center in Baghdad on Thursday after authorities urged Iraqis to help battle the insurgents.
The Islamic State's spokesman, Abu Mohammed al-Adnani, also threatened that the group's fighters will take the southern Iraqi Shiite cities of Karbala and Najaf, which hold two of the holiest shrines for Shiite Muslims.
"We will march toward Baghdad because there we have an account to settle," he urged followers in an audio recording posted on militant websites commonly used by the group. The statement could not be independently verified.
Al-Adnani also said that one of his group's top military commanders, Adnan Ismail Najm, better known as Abu Abdul-Rahman al-Bilawi al-Anbari, was killed in the recent battles in Iraq.
Al-Adnani said Najm worked closely with the former leader of al-Qaida in Iraq, Jordanian-born Abu Musab al-Zarqawi, who was killed by U.S. troops in 2006. Najm was later detained and spent years in prison before he was set free two years ago and prepared and commanded the operations that led to the latest incursions by the group in northern and central Iraq.
The militants are trying to expand into other areas too.
Hikmat, the Kurdish official, said some 20 pickups carrying Islamic State militants attacked peshmerga positions near the town of Sinjar. He said they were forced to retreat after four hours of clashes that began late Wednesday and left nine militants dead and four peshmerga members wounded.
Sinjar is 400 kilometers (250 miles) northwest of Baghdad in Ninevah province, outside of the semiautonomous Kurdish area, but is under Kurdish control.
Iran's foreign minister, Mohammad Javad Zarif, offered his country's support to Iraq in its "fight against terrorism" during a phone call with his Iraqi counterpart, Iranian state TV reported.
Shiite powerhouse Iran, which has built close ties with Iraq's postwar government, a day earlier said it was halting flights to Baghdad because of security concerns and has intensified security measures along its borders.
Iranian President Hassan Rouhani on Wednesday blasted the Islamic State as "barbaric" and said that his country's highest security body will hold an immediate meeting to review the developments in neighboring Iraq.
The Islamic State aims to create an Islamic emirate spanning both sides of the Iraq-Syria border. It has been able to push deep into parts of the Iraqi Sunni heartland once controlled by U.S. forces because police and military forces melted away after relatively brief clashes.
The White House said Wednesday that the United States was "deeply concerned" about the Islamic State's continued aggression.
Human Rights Watch expressed concern Thursday about the group's advances, noting its history of violence and other abuses. The rights group also called on Baghdad to deal with the crisis "without the brutal tactics for which civilians elsewhere in the country have long been paying a heavy price," deputy Middle East director Nadim Houry said.
There were no reliable estimates of casualties or the number of insurgents involved, though several hundred gunmen were involved in the Tikrit fight, said Mizhar Fleih, the deputy head of the municipal council of nearby Samarra. An even larger number of militants likely would have been needed to secure Mosul, a much bigger city.
Baghdad does not appear to be in imminent danger from a similar assault, although Sunni insurgents have stepped up car bombings and suicide attacks in the capital in recent months.
So far, Islamic State fighters have stuck to the Sunni heartland and former Sunni insurgent strongholds where people are already alienated by the Shiite-led government over allegations of discrimination and mistreatment. The militants also would likely meet far stronger resistance, not only from government forces but by Shiite militias if they tried to advance on the capital.
Mosul, the capital of Ninevah province, and the neighboring Sunni-dominated province of Anbar share a long and porous border with Syria, where the Islamic State is also active.
Mosul's fall was a heavy defeat for al-Maliki. His Shiite-dominated political bloc came first in April 30 parliamentary elections -- the first since the U.S. military withdrawal in 2011 -- but failed to gain a majority, forcing him to try to build a governing coalition.
In addition to being Saddam's hometown, Tikrit was a power base of his once-powerful Baath Party. The former dictator was captured by U.S. forces while hiding in a hole in the area and he is buried south of town in a tomb draped with the Saddam-era Iraqi flag.
Schreck reported from Dubai, United Arab Emirates. Associated Press Writer Bassem Mroue in Beirut and Nasser Karimi in Tehran contributed to this report.
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