Loud explosions and intense gunbattles were heard from inside the town on Sunday.
Kurdish peshmerga fighters last week launched the operation to retake Sinjar and opened up a passageway to Mt. Sinjar, overlooking the town, to evacuate some of the thousands of Yazidis trapped on the mountain by the fighting.
Meanwhile, an Iraqi official says Iraqi forces were fighting Sunday to retake the Tal Afar military airport from the IS group. He spoke on condition of anonymity as he was not authorized to talk to media.
The town of Tal Afar is to the east of Sinjar, strategically close to the Syrian border.
