BAGHDAD – Sunni militants launched a dawn raid Wednesday on a key Iraqi oil refinery they have been trying to take for days but were repelled by security forces, a commander on the scene said, as dozens of newly arrived U.S. military advisers and special operations forces began assessing the Iraqi forces in an effort to strengthen Baghdad's ability to confront the insurgency.
Prime Minister Nouri al-Maliki's government is struggling to repel advances led by militants of the Islamic State of Iraq and the Levant, a well-trained and mobile force thought to have some 10,000 fighters inside Iraq.
The response by government forces has so far been far short of a counteroffensive, restricted mostly to areas where Shiites are in danger of falling prey to the Sunni extremists or around a major Shiite shrine north of Baghdad.
Iraqi officials have told The Associated Press that al-Maliki is ready to at least temporarily concede the loss of large swaths of territory to Sunni insurgents as he deploys the military's best troops to defend Baghdad.
Shiite militias responding to a call to arms by Iraq's top cleric are also focused on protecting the capital and Shiite shrines, while Kurdish fighters have grabbed a long-coveted oil-rich city outside their self-ruled territory, ostensibly to defend it from the al-Qaida breakaway group.
Government forces backed by helicopter gunships have fought for a week to defend Iraq's largest oil refinery in Beiji, north of Baghdad.
The refinery is located in the heart of the Sunni-dominated areas in northern Iraq, where the militants have swallowed large swaths of land since June 10. Along with a nearby power plant, the refinery supplies Iraq with a third of its refined fuel and nearly a tenth of its electricity, according to Barclays analysts.
Militants attacked the site again early Wednesday but were beaten back by government forces, said Col. Ali al-Quraishi, the commander of Iraqi counterterror forces at the scene. He said his men exchanged fire with insurgents when they tried to attack a nearby oil pipeline, wounding one solider.
Across the border, Iran's semiofficial Fars news agency reported that three Iranian troops were killed in an attack Tuesday night by an unspecified "terrorist group" near the border with Iraq. While it is not clear which group was behind the attack in Iran's western Kermanshah province, the incident highlighted the risk of spillover from the Sunni militants' assault into Shiite powerhouse Iran.
Iran, which has strong ties with Iraq's Shiite-led government, has boosted border security amid advances by the militants.
President Barack Obama last week announced he would send as many as 300 advisers into Iraq to assess and advise Iraqi security forces. The U.S. Defense Department said Thursday that some of those personnel are now in Baghdad.
U.S. Navy Rear Adm. John Kirby said they included two teams of special forces and about 90 advisers, intelligence analysts, commandos and support personnel needed to set up a joint operations center in the Iraqi capital. Another four teams of special forces would arrive in the next few days, Kirby said.
They will evaluate the readiness of the Iraqi troops and their senior headquarters commanders in an effort to determine how best the U.S. can strengthen the security force and where other additional advisers might be needed. Iraqi officials said the U.S. advisers were expected to focus on the better units the Americans had closely worked with before pulling out.
Combined with approximately 360 other U.S. forces in and around the American Embassy in Baghdad to perform security, they would bring the total U.S military presence in Iraq to about 560.
In the face of militant advances that have virtually erased Iraq's western border with Syria and captured territory on the frontier with Jordan, al-Maliki's focus has been the defense of Baghdad, a majority Shiite city of 7 million fraught with growing tension. The city's Shiites fear they could be massacred and the revered al-Kazimiyah shrine destroyed if Islamic State fighters capture Baghdad. Sunni residents also fear the extremists, as well as Shiite militiamen in the city, who they worry could turn against them.
The militants have vowed to march to Baghdad and the holy Shiite cities of Najaf and Karbala, a threat that prompted the nation's top Shiite cleric, Grand Ayatollah Ali al-Sistani, to issue an urgent call to arms that has resonated with young Shiite men.
The military's best-trained and equipped forces have been deployed to bolster Baghdad's defenses, aided by U.S. intelligence on the militants' movements, according to the Iraqi officials, who are close to al-Maliki's inner circle and spoke on condition of anonymity to discuss such sensitive issues.
The number of troops normally deployed in Baghdad has doubled, they said, but declined to give a figure. Significant numbers are defending the Green Zone, the sprawling area on the west bank of the Tigris River that is home to al-Maliki's office, as well as the U.S. Embassy.
Iraq's best-trained and equipped force is a 10,000-strong outfit once nicknamed the "dirty division" that fought alongside the Americans for years against Sunni extremists and Shiite militiamen. Now it is stretched thin, with many of its men deployed in Anbar province in a months-long standoff with Sunni militants who have since January controlled the city of Fallujah, 30 miles (50 kilometers) west of Baghdad.
The Iraqi military, rife with corruption and torn by conflicting loyalties, lacks adequate air cover for its ground troops and armor, with the nation's infant air force operating two Cessna aircraft capable of firing U.S.-made Hellfire missiles. That leaves the army air wing of helicopter gunships stretched and overworked.
While Iraq's security forces number a whopping 1.1 million, with 700,000 in the police and the rest in the army, corruption, desertion and sectarian divisions have been a major problem. With a monthly salary of $700 for newly enlisted men, the forces have attracted many young Iraqis who would otherwise be unemployed. Once in, some bribe commanders so they can stay home and take a second job, lamented the officials.
Associated Press writers Hamza Hendawi in Baghdad, Adam Schreck in Dubai, United Arab Emirates, Amir Vahdat in Tehran, and Lolita C. Baldor and Bradley Klapper in Washington contributed to this report.