The blast in the multi-ethnic city, some 250 kilometres (155 miles) north of Baghdad, came as war-torn Iraq gears up for legislative elections on May 12.
Iraqi troops last year seized the vital oil-rich Kirkuk region from Kurdish forces after a controversial vote for independence in Iraq’s autonomous Kurdish zone.
Turkmens largely welcomed the return of government control forces, years after the Kurds took over the area amid the chaos of the Islamic State group’s march across Iraq in 2014.
Since the return of Baghdad’s forces, the region has seen clashes between Kurdish fighters and Turkmen units of the Hashed al-Shaabi paramilitary forces, officially controlled by the government.
Candidate Kahya is an advisor to Falah al-Fayadh, who official heads the Hashed.