Haider al-Abadi

Iraqi and Turkish officials said the 18 are employed by Nurol Insaat, a Turkish construction company contracted to build a sports complex in the sprawling Shiite district of Sadr City. The kidnappers stormed the construction site, where the workers were sleeping in caravans, breaking down doors and disarming the guards before taking the workers away, they said.

The Iraqi officials said an Iraqi national was kidnapped along with the Turks.

"Victory at Beiji is a crucial step toward ending Daesh's presence in Iraq," Haider al-Abadi told military and militia commanders during a visit to the area the day before, using an Arabic acronym for the extremist group.

The military retook the town of Beiji from the IS group in November, but government forces and allied Shiite militiamen there have come under mounting pressure in recent weeks. Militants now control up to half of the town and oil refinery to the north, a top commander told The Associated Press.

In a three-part message posted on his official Twitter account Tuesday, al-Abadi said that the council is committed "not to allow any attack on Turkey from Iraqi territory and called on Turkey to respect good relations."

Turkey launched a wave of airstrikes in Iraq last week targeting militants with the Kurdistan Workers Party, or PKK, in the country's northwest.