BAGHDAD — A suicide bomber killed 16 Iraqis yesterday outside a police station in an area of northern Iraq contested by Kurds and Arabs. The bomber blew himself up alongside police recruits in the town of Sinjar in Nineveh province. The dead included 14 recruits and two policemen, Brigadier General Khalil Juboori of the provincial police said.

An injured policeman said the police force had been warned the previous day of a potential attack. They had planned to cancel the recruitment drive. “While we were informing recruits not to gather … he [the suicide bomber] mingled with the recruits and blew himself up,” the policeman said.

Nineveh province’s capital, Mosul, has been the focus this month of an Iraqi army and police campaign to target Al Qaeda in Iraq fighters, who have used the city as a stronghold. However, Iraqi forces met little resistance, prompting speculation that most fighters had fled the city before the operation began almost three weeks ago.

The northern city and surrounding regions had already been a hotbed of violence amid festering tensions pitting Arabs against Kurds. Bombings last August in villages around Sinjar claimed the lives of nearly 500 people and were blamed on Al Qaeda in Iraq.

The Kurdistan region, which borders Nineveh, wants to annex areas surrounding Mosul as well as Sinjar, which is home to the Yazidi religious sect. Nineveh’s Sunni Arabs are fiercely opposed to the plan.