Iraqi troops and Shiite militias battled the Islamic State of Iraq and Syria (ISIS) Wednesday for a third day on the outskirts of militant-held Tikrit, unable to advance further on Saddam Hussein's hometown as roadside mines and suicide attacks slowed their progress.
Soldiers found some 100 mines and bombs scattered along a 5-mile stretch of road on the way to the strategic city on the Tigris River, Salahuddin deputy governor Ammar Hikmat said Tuesday.
The discovery underlined how the battle for Tikrit likely will pivot on allied Iraqi forces' ability to counter such weapons, a mainstay of al Qaeda in Iraq, ISIS' predecessor, as it fought American forces following their 2003 invasion of the country.
In an unusual alliance bridging the divide between the main sects of Islam, Iranian-backed Shiite militias and Sunni tribes have joined Iraq's military in the operation to retake Saddam Hussein's hometown from ISIS, while the U.S.-led coalition has remained on the sidelines.
CBS News' Holly Williams says nearly 30,000 troops and allied militia members are on the ground, according to officials -- the biggest offensive since ISIS swept across northern Iraq last year.
But, adds Williams, it looks more like a rag-tag army than a well-disciplined national military.
If the unlikely coalition fails to take Tikrit, it could slow down plans to recapture Mosul, Iraq's second biggest city, which lies just to the north.
U.S. military officials have said a coordinated military mission to retake Mosul will likely begin in April or May and involve up to 25,000 Iraqi troops. But the Americans have cautioned that if the Iraqis aren't ready, the offensive could be delayed.
The bombs are "the main obstacle in the way of the attacking forces, which have to wait for bomb experts or to go around the area," Hikmat told The Associated Press. "And this costs time."
Extremists from ISIS, which holds both a third of Iraq and neighboring Syria in its self-declared caliphate, have littered major roadways and routes with mines. Such mines allow the extremists to slow any ground advance and require painstaking clearing operations before troops can safely move through.
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Without U.S. help, Iraq struggles to push into Tikrit