Islamic State militants armed with assault rifles and explosives attacked targets in and around the northern Iraqi city of Kirkuk early on Friday in an assault that appeared aimed at diverting Iraqi security forces from a massive offensive against the IS-held city of Mosul.

At least 11 workers, including two Iranians, were killed when IS militants stormed a power plant north of Kirkuk and then blew themselves up.

Multiple explosions meanwhile rocked the city, and gunbattles were ongoing, said witnesses in Kirkuk. Much of the fighting was centered on a government compound in the city. They said the streets were largely deserted out of fear of militant snipers.