Iraqi local outlets says the security forces are approaching Tikrit city from five sides on Monday.
"Al-Dur hometown of Izzat al-Duri, and village of al-Bu Khadu, home to relatives of ISIS leader and self-proclaimed caliph Abu Bakr al-Baghdadi, liberated by allied forces."
Security forces would also move to take the cities of al-Alam in the offensive, which aims to bring the entire province of Salah al-Din back under government control, officials said.
Iraq's armed forces, backed by Shi'ite militia, attacked ISIS strongholds north of Baghdad on Monday at the start of a campaign aimed at driving them out of the province of Salahuddin.
A source at the local military command said forces advanced north from Samarra towards the town of al-Dour, which officials describe as an ISIS bastion, and Tikrit, which lies about 40 km north of Samarra.
Al-Dur is the hometown of Izzat al-Duri, a key aide to former ruler Saddam and a leader of a Baathist militia which joined in the ISIS-led offensive last summer.Security forces had captured the village of al-Bu Khadu, home to relatives of ISIS leader and self-proclaimed caliph Abu Bakr al-Baghdadi.
EXCLUSIVE CLICK TO WATCH Tikrit Biggest Operation Begins, Army, Militias Advance on South and East
Hours ahead of the operation, Prime Minister Haider al-Abadi, a Shiite, called on ISIS supporters and tribal fighters to abandon the extremist group, offering what he described as “the last chance” and promising them a pardon.
Al-Abadi offered what he called “the last chance” for ISIS supporters and tribal fighters, promising them a pardon. “The city will soon return to its people,” he added.
According to local Security source “The Iraqi Army forces liberated the residential areas in al-Dor and al-Qadissiya districts from the ISIS Terrorists.”
Also and Iraqi aviation began making progress on ISIS terrorist organization in the areas south of Tikrit.
Another source said that the security forces and fighters from the popular fighters and other tribes managed to control "Po Hassani" area in al-Dour district (the birthplace of former Vice dictator , Izzat al-Duri) south of Tikrit city, indicating that the Iraqi army aviation and artillery are still bombing the sites of ISIS organization to storm it, Shafaghna reports.
Tikrit Biggest Operation Begins, Army, Militias Advance on South and East
Al-Iraqiya television said that the forces were attacking Tikrit from different directions, backed by artillery and airstrikes by Iraqi fighter jets. It said the militants were dislodged from some areas outside the city, but gave no details.
Any operation to take Mosul likely would require Iraq to seize Tikrit first because of its strategic location for military enforcements.
It is reported that former members of Iraq’s outlawed Baath party, loyalists to Saddam, joined the ISIS group against Tikrit offensive as well as other Sunnis tribes who support radicals.