Iraqis wave Kurdish flags as they gather in support of the upcoming independence referendum and against the parliament's sacking of the governor of the oil-rich state the previous week during a rally in Kirkuk on September 19, 2017. (AFP Photo)

BAGHDAD, Sept. 19 (Xinhua) -- Clashes erupted in Iraq's ethnically-mixed city of Kirkuk on Tuesday amid preparations for the Kurdish independence referendum next week, a local Turkmen official said.

The Iraqi Kurds plan to hold the referendum on Sept. 25 in three governorates as well as in disputed areas that are controlled by Kurdish forces but claimed by Baghdad, including the oil-rich province of Kirkuk.

Baghdad, Turkey, Iran and the international community have rejected the vote and asked the Kurds to call it off to avoid further destabilizing the region.

Gunmen on motorcycles opened fire on the offices of the Iraqi Turkmen Front. The guards returned fire, killing one and wounding two of the assailants.

Kirkuk is home to Arabs, Kurds, Turkmen and Christians. Kurdish forces took control of the province and other disputed areas in the summer of 2014, when the Islamic State group swept across northern and central Iraq and the Iraqi armed forces crumbled.

On Monday, Iraq's top court suspended the northern Kurdish region's referendum on independence.