Iraqi forces continued to press a major offensive to retake Tikrit from Islamic State militants on Wednesday, although progress has slowed as they encounter booby traps and snipers.
The 30,000-strong mixed force, made up of government troops and security forces alongside Shia militias and Sunni tribes, launched the assault early on Monday, backed by attack jets and helicopters. Commanders from regional Shia powerhouse Iran have also taken a leading role in the operation, a development described by the US military as "positive" but which has also raised concerns about the risk of fanning sectarianism.
So far they have advanced on towns to the north and south of Tikrit as well as from the east, but the Islamic State is understood to remain in control the city itself.
The attackers vastly outnumber the occupying Islamic State fighters, so the extremists have resorted to insurgency tactics, such as IEDs, suicide bombs and snipers to stall the advance, a senior officer involved in the offensive told AFP. "They are using urban warfare and snipers, so we are advancing in a cautious and delicate way, and we need more time," the officer said. The agency also quoted Iraqi Lt. Gen. Abdel Amir al-Zaidi as saying that the current strategy was to surround and cut off Islamic State fighters in the city, block their supply lines then "pounce."
The Islamic State announced on Tuesday that an American citizen identified only by his nom de guerre Abu Dawud al-Amriki had launched a suicide attack on Iraqi forces in Samarra, Salaheddin province's other major city.
Tikrit, the birthplace of deceased Iraqi dictator Saddam Hussein, is around 100 miles north of Baghdad and was seized by Islamic State in June 2014 as the group swept across the north of the country in a shock offensive. Government forces have made several unsuccessful attempts to retake the city since, but this is the largest yet and comes as Islamic State has suffered defeats elsewhere in recent months, including the nearby oil refinery town of Baiji.
If Tikrit is retaken, it would be a propaganda and tactical victory for Iraqi forces, which are also preparing for an assault on the country's second city of Mosul, and would demonstrate the efficacy of such a large combined army and militia force.
The Iraqi defense ministry released footage of the offensive on Tuesday as it claimed a number of gains.
Prime Minister Haider al-Abadi announced the assault on Sunday evening at a news conference in Samarra. He added that security forces should ensure that civilians be spared during the fighting and, on his Facebook page, said that civilian lives and property must be protected. Abadi was seemingly referring to fears that Shia militias could target Tikrit's Sunnis in reprisal attacks.
The Islamic State kidnapped then executed more than 1,000 predominantly Shia recruits from the Camp Speicher military base close to Tikrit during its June 2014 offensive. Shia militias vowed revenge and often accuse local Sunni tribes of involvement in the killings.
Hadi al-Ameri, transport minister and head of the Badr Organization — an armed political movement closely associated with Iran — made the link explicit during a speech on Saturday in which he said those living in predominantly Sunni Tikrit should leave their homes to allow pro-government forces to "wrap up the battle of the revenge for Speicher."
Some Sunni tribes and local supporters of Hussein's Baath Party sided with the Islamic State against the government last year. However, Abadi hinted that those who had could be offered amnesty, urging fighters "who were misled and made a mistake to lay down their arms," but also warning that this could be their "last chance."
Heavy involvement in the operation from Iran could also risk inflaming sectarian tensions. The commander of the country's covert Al-Quds Force Qassem Soleimani is in Salaheddin and playing a leadership role in the assault, according a number of reports.
Officers with the Iranian Revolutionary Guards were also involved in command roles before the operation was launched, according to sources cited by BBC Persian. A commander with Shiite Khorasani Brigade militia said that Iranian forces had been training and "morally preparing" fighters for the offensive, it reported.
Iran was not invited to join a US-led international coalition dedicated to destroying Islamic State, although it has played a major role in the conflict nonetheless. A number of Shia militias operating in Iraq openly admit to taking orders from Tehran, and others are known to receive equipment and training. Iran also dispatched military advisers to the country, and has even supplied Iraq with attack aircraft.
Iranian Foreign Ministry Spokeswoman Marziyeh Afkham denied on Wednesday that combat forces had been sent also, according to the country's semi-official FARS News Agency.
There appears to be little American involvement in the Tikrit offensive, and it has not been participated in air support, despite the extensive strikes against Islamic State targets it has undertaken since August elsewhere in Iraq.
Nevertheless, the US may not be opposed to this level of involvement from its longtime foe, officials say. The chairman of the US Joint Chiefs of Staff, Gen. Martin Dempsey told the Senate Armed Services Committee on Tuesday that Iranian involvement could be "positive" provided that the Shia powerhouse's presence does not lead to sectarian violence.
"This is the most overt conduct of Iranian support, in the form of artillery and other things," Dempsey said. "Frankly, it will only be a problem if it results in sectarianism."
Meanwhile US Central Command head Gen. Lloyd Austin said America "saw this coming" for some time before the Tikrit assault began, but added that there is no cooperation between American and Iranian forces. "It's a logical progression of what they have been doing in the east of the country, but we don't coordinate with them," he told the House Armed Services Committee.
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