Daesh suicide attackers killed 16 people at an Iranian-run construction site in the Iraqi town of Dibis, north of Kirkuk on Friday as coalition troops advanced on the Daesh terrorist group's bastion Mosul, a senior Iraqi official said.
"Three suicide bombers attacked the power plant at around 6:00 am (0300 GMT), killing 12 Iraqi administrators and engineers and four Iranian technicians," Dibis mayor Abdullah Nureddin al-Salehi said.
Three bombers had infiltrated the power plant being built by an Iranian company near Dibis, a town around 40 kilometres (25 miles) northwest of Kirkuk, the mayor said.
He said the attack led to clashes with security forces, who were able to kill one of the bombers before he detonated his vest. The other two blew themselves up once they were surrounded.
In addition, at least six policemen and 12 Daesh terrorists had been killed in fighting, mostly in southern neighbourhoods, a police officer told AFP.
"There are sporadic clashes between the security forces and Daesh," he added.
Hours earlier, a commando of suicide bombers armed with rifles attacked several locations in Kirkuk, an ethnically divided city 240 kilometres (150 miles) north of Baghdad, security sources said.
In another incident, a Kurdish intelligence officer said four suicide attackers bombed the main police headquarters in Kirkuk at around 3:00 am (2400 GMT) on Thursday.
"The security forces managed to shoot one of them dead, the other three blew themselves up," he said.
According to the officer, members of Daesh also attacked several other targets in the south of the city, which sparked clashes with security forces that continued for five hours.
A Kirkuk official said that a curfew was placed on the city.