BAGHDAD (AP) -- A trio of bombs exploded on Sunday in the northwest Iraqi city of Mosul, killing four security officers and wounding seven other people, officials said.
The violence began with a car bomb that killed two soldiers and wounded another five, police officials said. A second bomb, which was placed under a vehicle, exploded, wounding two people. Later, a roadside bomb killed a police officer and a soldier.
A health official confirmed the casualties in an industrial area of the city, 360 kilometers (225 miles) northwest of Baghdad.
The police and health officials spoke anonymously because they weren't allowed to talk to media.
A surge in violence is expected in Iraq in the lead up to provincial elections on April 20.
Mosul is the capital of Ninevah province and the Iraqi government has already delayed elections throughout the province because of violence. The elections also have been delayed in the Sunni-dominated Anbar province in western Iraq.
There was no immediate claim of responsibility for the bombings.
The attacks were similar to others conducted by Sunni militants -- often tied to al-Qaida -- who use suicide attacks, car bombs and roadside explosions to try to erode confidence in the Shiite-led government.
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