KIRKUK, Iraq, Jan. 2 (Xinhua) -- Unidentified gunmen shot dead an official of a Turkoman party in the ethnically mixed city of Kirkuk in northern Iraq on Tuesday, a security source said.

The attack occurred in the evening at a marketplace in al-Askari district when armed men opened fire on Alaa al-Din al-Salihi, head of branch of the Turkoman Front in the district, the source told Xinhua on condition of anonymity.

Hassan Turan, deputy head of the front which is an umbrella for several Turkoman parties, told reporters that Salihi's assassination is part of a series of attacks that targeted the Turkoman minority and their front's headquarters.

"The attacks during the past days also targeted the Turkoman districts in Kirkuk by mortar rounds," Turan said.

The ethnically mixed city of Kirkuk, some 250 km north of Baghdad, is part of the disputed areas between the central government and the semi-autonomous region of Kurdistan.

Disagreements between Baghdad and the Kurdish region have been high for years, as the ethnic Kurds consider the northern oil-rich province of Kirkuk and parts of Nineveh, Diyala and Salahudin provinces as disputed areas and want them to be incorporated into their region, a move fiercely opposed by the Arabs and Turkomans and by Baghdad government.

In mid-October, the Iraqi federal security forces took control of Kirkuk province, including its oil oilfields and military bases, after the withdrawal of the Kurdish Peshmerga forces.

Since then, the city witnessed attacks by gunmen against the Iraqi forces and civilians from time to time, while the western and southern part of the oil-rich Kirkuk province have been witnessing attacks by remnants of Islamic State militants.