Iraq on Monday held a state funeral for 41 Yazidis killed by the Islamic State group in 2014 and recently identified by authorities after complex and lengthy DNA tests.

After seizing swathes of Iraq in 2014, IS jihadists carried out horrific massacres, including in the northern region of Sinjar where the Kurdish-speaking Yazidi minority has long been rooted.

The group targeted the ethno-religious minority, systematically killing thousands of men and forcing women into sexual slavery.

After Iraqi authorities declared victory over the jihadists in 2017, scores of mass graves were discovered across the country, setting off a long and painstaking process of identifying the bodies.

In Baghdad, portraits of the victims and their coffins, covered with the Iraqi flag and flower wreaths, were paraded on army pick-up trucks at the Iraqi capital's iconic Martyrs monument.

Family members and Yazidi officials attended the ceremony.

The identification of Monday's 41 victims brings the total number of Yazidis found and returned to their families to 188, health ministry spokesperson Saif al-Badr told AFP.

Work continues through a "complex and expensive process" of DNA testing to identify the victims, he added.

The bodies were exhumed from a mass grave dating back to "massacres committed in 2014 by the terrorist organisation IS", the director of Iraq's forensic authority Zaid Ali Abbas told AFP.

He highlighted the challenges of collecting samples and setting up a database when "a large number of the victims' relatives are abroad".

Yazidi MP Vian Dakhil decried "sluggishness regarding government procedures and DNA testing", noting the "large number (of victims) who have still not been identified."

"Unfortunately, it seems that the Sinjar file is not one of the major concerns of successive governments since 2014," she added, pointing to insufficient public funding dedicated to the process.

Last May, authorities organised similar funerals for 78 victims of IS, namely Shiite prisoners captured by the jihadists in northern Iraq's Badush prison before being executed.

The more than 200 mass graves left behind by the jihadists, which are still being exhumed, could contain up to 12,000 bodies, according to the United Nations.

More than 2,700 Yazidis remain missing, according to the International Organization for Migration.