Ahmad Al-Rubaye | AFP | Getty Images
Iraqi forces launched an operation on Tuesday to drive Islamic State militants out of Tikrit, hometown of executed former dictator Saddam Hussein, officers in the operations room told Reuters.
They were advancing rapidly from the south but were slowed by landmines, roadside bombs and snipers in the west, said an army major and a police captain.
Read MoreUS conductsairstrikes in Iraq near Irbil and Mosul
Iraqi and Kurdish forces have been encouraged by the first U.S. air strikes in the country - launched against the hardline Sunni insurgents - since American troops withdrew in 2011.
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