Baghdad says Iraqi troops have reached the center of Tikrit after securing the city's southern and western sections from Islamic State (IS) militants.
Prime Minister Haidar al-Abadi said on March 31 that security forces were "moving toward the control of the whole city," located north of Baghdad.
Abadi gave credit for the development to the Iraqi Army and police, supported by Iraqi and U.S.-led air strikes, along with fighters from Shi'ite militia groups and Sunni tribes.
He later announced the "liberation" of Tikrit from IS occupation on Twitter, but reports said fighting for large parts of the city was ongoing.
Shi'ite militia returned to battle after they had frozen their operations last week.
Shi'ite militiamen have provided the largest number of fighters to the offensive in the area that began on March 2.
But operations slowed after weeks of heavy casualties and tensions within the government and with U.S. officials over Iran's prominent role supporting the Shi'ite militia.
IS fighters stormed into the hometown of the late Iraqi dictator Saddam Hussein in June 2014 during a rapid advance across northern and western Iraq.