Masked men in military uniforms have kidnapped 16 Turkish workers and engineers in Baghdad, bundling them into several pick-up trucks and speeding away, Iraqi security officials said.

They said the 16 are employed by 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, and disarmed guards before taking the workers away.

There were no reports of violence.

Turkey's Foreign Ministry confirmed 16 Turkish nationals were kidnapped and said it was in constant contact with Iraqi authorities over the incident. It said that for security reasons it cannot reveal details of the workers or who employed them.

Interior Ministry spokesman Saad Maan said a contingent of security forces has been tasked with tracking down the kidnappers.

The identity or motives of the kidnappers are not yet clear.

Turkey recently began air strikes against the Islamic State group in northern Iraq and allows US planes to use bases in south-eastern Turkey to strike the Sunni extremist group.

It launched a simultaneous air campaign in northern Iraq against the Kurdistan Workers' Party, or PKK, a Kurdish militant group.

The style and scale of the kidnapping was reminiscent of the sectarian violence in Baghdad in 2006 and 2007, when Sunni and Shiite militants kidnapped followers of the other sect. In most cases, the bodies of those kidnapped were found a day or two later with marks of torture and a bullet wound to the head.

Baghdad has been torn by violence for over a decade now, with roadside bombs, suicide attacks and assassinations occurring almost daily.