Curfew imposed in Kirkuk amid fears over ethnic tension
The city, which is ethnically mixed with Kurds, Arabs and Turkmen, took place in the referendum opposed by Baghdad on Monday.
"A total curfew has been imposed until further notice" in the city centre and in Arab and Turkmen areas "to ensure security, monitor the situation and protect the citizens of Kirkuk," police Colonel Afrasiyao Kader told AFP.
Soon after the announcement was made, security forces affiliated with Iraq's interior ministry were spotted on the streets of the city by an AFP photographer.
The curfew was reportedly imposed to prevent clashes between the city's different ethnic groups, a police source said.
It was not enforced in Kurdish districts of Kirkuk.
Despite warnings about holding the referendum in disputed areas, voting took place in the oil-rich Kirkuk province. The province is not part of the three-province Kurdish autonomous region recognised by Iraq's government in Baghdad.
World powers opposed to the referendum, including the United States, had urged the Kurdish leadership in Erbil not to hold the referendum in disputed provinces.
The province's Kurdish governor, Najm Eddine Karim, was sacked by Baghdad last week after his provincial council decided to take part in the poll, however he has refused to vacate the post.
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Monday saw voters turn out in large numbers in the northern province, where Kurdish flags were seen waving amid the playing of Kurdish music and Kurdistan's national anthem.
This carnival atmosphere sharply contrasted the quiet streets of Kirkuk's Arab and Turkmen areas.
Kurdish nationalists claim Kirkuk as their own, arguing that Iraq's late dictator Saddam Hussein chased Kurds out and replaced them with Arab residents.