Report said peshmerga forces from Iraq's autonomous Kurdish region attacked villages near Bashiqa at dawn.
AFP reporters said peshmerga forces from Iraq's autonomous Kurdish region backed by air strikes from a US-led coalition attacked villages near Bashiqa at dawn.
In the village of Nawaran, Iranian Kurdish rebels from the Kurdistan Freedom Party (PAK) were also involved in the assault, some of them at the very front of the fighting.
The peshmerga command issued a statement saying the "large-scale operation" was launched at 6:00 am (0300 GMT) north and northeast of Mosul.
"The objectives are to clear a number of nearby villages and secure control of strategic areas to further restrict ISIL's movements," it said, using an alternative acronym for IS.
It said the operation had three different fronts and was "designed to tighten the noose" around IS in Mosul following recent gains by peshmerga and Iraqi federal forces east and south of the city.