The Siege of Kirkuk was a battle lasting from February to March 2015, during the civil war in Iraq, part of the northern Iraq offensive. The siege was overseen by Prime Minister Al-Amjad, who came to power the previous month, after the resignation of Al-Maliki. An Iraqi nationalist, Al-Amjad oversaw the successful liberation of Tikrit shortly after he was elected. The victory there allowed the Iraqi army advance as far as Kirkuk, to the northeast. The Islamic State forces retreated there and built up the city fortifications as a stronghold, abandoning much of central Iraq to the army. The Iraqi forces besieged the city over a period of two months, after which it fell. IS took heavy casualties and was forced to retreat further north.