KIRKUK, Iraq (AFP) - Iraqi security forces have killed 48 of the gunmen who stormed parts of Kirkuk in a shock attack claimed by the Islamic State in Iraq and Syria (ISIS) group, the city's police chief said.

"Forty-eight Daesh (ISIS) terrorists have been killed in the clashes," Brigadier General Khattab Omar Aref told AFP, adding that some of them blew themselves up when the security forces cornered them.

Special counter-terrorism and intelligence units were hunting down some of the dozens of ISIS fighters who stormed public buildings in the early hours of Friday.

Clashes have been taking place almost uninterrupted since and the city, which lies some 240 kilometres north of Baghdad, remains under curfew.

A senior interior ministry official said that at least 46 other people had been killed in the ISIS raid and ensuing clashes, mostly members of the security forces.

"The security forces control the situation now but there are still pockets of jihadists in some southern and eastern neighbourhoods," Aref said.

"We have foiled this large Daesh (ISIS) plot, which was to take control of government buildings, including security headquarters," he said.

"They were denied just like they are being defeated on the outskirts of Mosul," the police chief said, in reference to the ongoing offensive by tens of thousands of Iraqi forces to wrest back the city of Mosul, ISIS's last major stronghold in Iraq.