Iraqi Prime Minister Haider al-Abadi has called for Iranian-allied Shiite militiamen to help drive Islamic State extremists from Ramadi, the capital of Iraq's vast Sunni-dominated Anbar province.
Sunday's fall of the city 70 miles (115 kilometers) west of Baghdad was the biggest blow in the fight against the group since it overran much of the north and west of Iraq last summer.
A look at the militias:
Who are the militiamen?
There are a number of different Shiite militias active in Iraq, and they make up the bulk of the so-called Popular Mobilization Units called up to resist the IS group last year. They include Asaib Ahl al-Haq, or the "League of the Righteous," and the Badr Brigades, which is led by former Transportation Minister Hadi al-Amiri. Other militias include the Hezbollah Brigades, which is separate from Lebanon's Hezbollah group but also has ties to Iran, and the Peace Brigades, which is loyal to anti-U.S. cleric Muqtada al-Sadr. Shiite militias played a key role in driving IS extremists from the northern city of Tikrit and other areas, raising hopes they can prove effective in Anbar too.
What is Iran's role?
The militias each have ties to Iran, the Shiite powerhouse across Iraq's border. The Islamic Republic has built an increasingly close relationship with Iraq's Shiite-dominated leadership after the 2003 U.S.-led invasion that toppled Sunni strongman Saddam Hussein, and Tehran's support for the militias are a way to enhance its power in the country. The threat posed by the IS group has only enhanced Iran's role, raising alarm in Saudi Arabia and other Sunni-led Gulf states. Tehran has deployed Gen. Qassem Soleimani, the commander of the Quds Force, and other military advisers to Iraq to help coordinate the fight. The force Soleimani leads is a special unit of Iran's elite Revolutionary Guard that is responsible for external operations.
Why use the militias?
The militias bring additional firepower and much-needed fighting spirit to the battle. The U.S. spent billions of dollars training and equipping the Iraqi military between 2003 and 2011. But the army and police remain hobbled by spotty levels of professionalism, deep-seated corruption and low morale, particularly after their stunning collapse amid the IS onslaught in June 2014. The loss of Ramadi was reminiscent of last year's rout, with Iraqi forces abandoning their posts and American-supplied equipment despite the help of U.S. airstrikes as the jihadists made a final push to take the city.
Will the militias' involvement make things worse?
This is a big risk. Several of the militias fighting the IS group took part in retaliatory sectarian killings that roiled Iraq after the 2003 invasion. That bloodshed, which at its peak in 2006 and 2007 threatened to push Iraq to the brink of civil war, left deep scars in Iraqi society. Many Sunni Iraqis, even if they don't side with the IS group, bristle at the rising influence of the militias and fear retribution from them. Rights activists and residents have blamed militias for looting, vandalism and other crimes in Sunni communities that they have helped retake from the IS group. Al-Abadi has vowed to safeguard Iraqis living in areas liberated from the militant group, pledging last month that their property and rights would be respected.
What about the Sunnis?
Sunni tribal fighters, backed by U.S. troops, were instrumental in turning the tide against the Iraqi branch of al-Qaida that IS evolved from in the years before the 2011 U.S. military withdrawal. Many still oppose the group — IS fighters have been going door-to-door in Ramadi searching for police and pro-government Sunni fighters as it tries to solidify control with deadly purges. But distrust against Iraq's Shiite-led government also runs deep. Many Sunnis feel marginalized and resent Baghdad's reluctance to better arm the tribesmen, although sentiments may be changing. The Cabinet said Tuesday it would give them weapons in coordination with the local government.
Associated Press writer Sameer N. Yacoub in Baghdad contributed reporting.