Fierce clashes outside Iraq's Tikrit after new offensive

           Iraqi troops fought on Tuesday with Islamic State extremists south of the militant-held city of Tikrit but their offensive to retake Saddam Hussein's hometown was slowed by roadside bombs, local officials said.

Backed by Iranian-backed Shiite militias and advisers along with Sunni tribal fighters, government forces made little headway on the second day of a large-scale military operation to recapture Tikrit, which fell to the Islamic State group last summer, two local officials said.

Fierce clashes were underway mainly outside the town of al-Dour, south of Tikrit, while government troops were shelling militant bases inside the city, they said.

The officials spoke anonymously as they were not authorized to brief media.

The military operation is seen as a litmus test for the capability of Iraqi troops to dislodge the militants from major cities they conquered in the country's Sunni heartland in the north and west during an onslaught last summer. Previous attempts to capture Tikrit all failed because of tough resistance from the militants.

Tikrit, the provincial capital of Salahuddin province, is located 80 miles (130 kilometers) north of Baghdad. It was taken by the Islamic State group along with the northern second-largest city Mosul during last year's fighting.

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. On Monday, Iraqi and U.S. officials said the U.S.-led coalition was not involved in the Tikrit operation and had not been asked to carry out airstrikes.

Also Monday, Iran's semi-official Fars news agency reported Iranian Gen. Ghasem Soleimani, the commander of the elite Revolutionary Guard's Quds Force, was taking part in the offensive. Soleimani has emerged as the chief tactician in Iraq's fight against the Sunni militants.

Gen. Abdul-Wahab al-Saadi, the military commander of the Salahuddin region told Iraqi state TV that troops would need some time to enter the city of Tikrit.