Updated

Iraq's special forces have begun an assault on Mosul, part of operations to drive the Islamic State group from the country's second city.

Troops have opened up with artillery, tank and machine gun fire on IS positions on the edge of the Gogjali neighborhood, with the extremists responding occasionally with rocket-propelled grenades. From the nearby village of Bazwaya, smoke could be seen rising from buildings on the city's edge, where shells were landing.

Brig. Gen. Haider Fadhil of the special forces says the operation began Tuesday morning.

For over two weeks, Iraqi forces and their Kurdish allies, Sunni tribesmen and Shiite militias have been converging on Mosul from all directions to drive IS from the city.

The operation is expected to take weeks, if not months.