Baghdad - A coalition of Shia militias, Iraqi government forces, and volunteers are in the midst of a major military operation to retake the city of Tikrit from the Islamic State of Iraq and the Levant (ISIL) that controlled it since last June.
On Sunday, fighting intensified to the north and south of the city perhaps best known as Saddam Hussein's hometown.Iraqi security forces vowed to reach the centre of Tikrit within 48 hours.
So far, the campaign, according to military officials, looks to be succeeding, expelling ISIL fighters from areas east and south of Tikrit.
This development, according to analysts, reflects unprecedented coordination between the Iraqi military, the popular mobilisation forces, and anti-ISIL Sunni tribesmen.
The anti-ISIL forces are currently surrounding the city of Tikrit from all directions, Iraqi government officials and military officers told Al Jazeera.
"The troops have entered the city [Tikrit] from two directions, the northern and southern districts, but the advance is slow because of the snipers and the booby traps," Jasim Ataiya, the deputy governor of Salahuddin province, told Al Jazeera.
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Meanwhile, other troops outside Salahuddin province have been launching small-scale offensives on ISIL-held territory in Anbar province, Kirkuk, and the outskirts of Mosul and northern Baghdad in order to distract ISIL fighters and cut off the group's supply routes.
"When you deal with the enemy [ISIL] for a long time, you get to know its tactics and weak points. Now we can say we definitely know how to fight [ISIL] and defeat them," said General Dhamin Thamar, who led the troops that captured Al-Alam town, located just north of Tikrit.
The campaign, which was launched two weeks ago, marks Iraq's biggest offensive to date against ISIL. The goal is to regain control of religiously and ethnically diverse Salahuddin province, which was captured by ISIL last summer.
ISIL currently controls a swath of land stretching across much of eastern Syria and western and northern Iraq, and enjoys the support of some of Iraq's Sunni population, that were marginalised during the rule of former Iraqi Prime Minister Nouri al-Maliki.
Battle-hardened militias including the Badr Organisation, Asa'ib Ahl al-Haq, and Kata'ib Imam Ali are said to be taking the lead in the campaign for Tikrit.
However, regular Iraqi government forces and about 1,500 anti-ISIL Sunni tribesmen are fighting alongside them, as well as volunteers from many sects and ethnicities.
The anti-ISIL militias and volunteers, collectively known as the Popular Mobilisation forces, is led by Hadi al-Amiri, the head of the Badr Organisation, who is said to be coordinating closely with the Iraqi army and federal police.
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Many analysts say the battle for Tikrit has brought into sharp focus the role played by Iran in fighting ISIL in Iraq. Iran has reportedly funded, trained and equipped many of these militias, and has sent dozens of senior military commanders to advise the Popular Mobilisation fighters.
As a result, Iraq's militias are armed with weapons that the Iraqi military has not possessed in large quantities since 2003, when the US-led invasion of Iraq destroyed much of the country's military arsenal.
Last week, al-Amiri said in TV interviews aired on the al-Ghadeer and al-Forat stations that "about 100 Iranian advisors had participated in the fighting against ISIL in Diyala and Salahuddin provinces, and they are continuing [working] with us, for free".
According to sources close to Shia militias, Major General Qassim Sulaimani, head of the Iranian Revolutionary Guard Corps' elite Quds Force, was on the ground and supervising a part of the Tikrit battle for the past few days.
"It was the first time that, I feel, the superiority is in favour of the Iraqi troops," Misha'an al-Jobouri, a Sunni lawmaker who is commanding Sunni tribesmen in the battle, told Al Jazeera. Most of the Sunnis fighting against ISIL are from the al-Jobour tribe, though others come from the al-Ubaid, al-Jumaila, Dulaim and Tikarta tribes.
When you deal with the enemy for a long time, you get to know its tactics and weak points. Now we can say we definitely know how to fight [ISIL] and defeat them.
"The [Iraqi] Ministry of Defence was incapable of providing enough weapons, but Iran has delivered all the required weapons and ammunition," said Jobouri. "When I went to [the battlefield] and saw the weapons, I was looking for Qassim Sulaimani, to thank him."
US officials appear to be concerned about the growing role that Iran is playing in the war against ISIL.
The US-led military coalition against ISIL, which has been carrying out airstrikes against the armed group, has not participated in the campaign, and has not been asked for air support in the fight for Tikrit.
General Martin Dempsey, the chairman of the US Joint Chiefs of Staff, told US senators at a hearing on March 11 that the Tikrit operation could signal a new level of Iranian involvement in Iraq.
"Iran and its proxies have been inside Iraq since 2004," said Dempsey.
"This is the most overt conduct of Iranian support in the form of artillery and other things. Frankly, it will only be a problem if it results in sectarianism."
Shia militias in Iraq have been accused of mass killings of Sunnis suspected of ties to groups like ISIL.
In late January, for instance, 72 Sunnis were shot dead in northeastern Baquba province, in a massacre believed to have been carried out by Shia militias.
US officials said that despite the participation of some Iraqi Sunni tribes in the campaign in Salahuddin province, serious concerns remain as to how armed groups will treat inhabitants of these areas.
"We're watching carefully. If this becomes an excuse to ethnic cleanse, then our campaign has a problem," General Dempsey told the US Senate last week.
Nevertheless, the general predicted that ISIL would lose Tikrit. "There's no doubt that the combination of the Popular Mobilisation forces and the Iraqi security forces, they’re going to run ISIL out of Tikrit," he said.
Source: Al Jazeera