The Iraqi Army, backed by Shiite, Sunni, and Iranian fighters, reportedly captured villages and oil fields east of the Islamic State-held city of Tikrit on Wednesday, cutting off a key supply route for the militants.

A military source told the BBC that Iraqi forces have taken control of the village of al-Maibdi, on the road to the Kurdish-controlled city of Kirkuk, and the nearby Ajil and Alas oil fields. The road is a key supply route for ISIS between the Salahuddin and Diyala provinces, the source added.

The villages of Siha and Mazraat al-Rahim, north of Tikrit, also have been reclaimed, another official told All Iraq News, in the third day of an operation to take back the city.

Iraqi forces are looking to encircle ISIS fighters in Tikrit before moving in, but they have not yet breached the militants’ defenses.

Tikrit is an Iraqi stronghold of the extremist group, along with the nearby town of al-Dour, which was surrounded by Iraqi forces on Tuesday, military officials told the BBC.

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