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BAGHDAD, May 5 (Reuters) - A suicide bomber killed nine police recruits and wounded 13 others when he detonated his explosive-packed vest outside an Iraqi army base west of Baghdad on Saturday, an Iraqi army source said.

The blast occurred near the Abu Ghraib prison west in Anbar province. Another army source confirmed the suicide attack but had no precise casualty figures.

Insurgents have repeatedly targeted U.S.-trained Iraqi security forces and recruitment centres. They have recently stepped up attacks in Sunni Arab Anbar after many tribes began recruiting locals in a bid to expel al Qaeda militants from the province.

Last month, a female suicide bomber killed 17 police recruits in the town of Muqdadiya, northeast of Baghdad.

A security crackdown launched in February has reduced sectarian killings in the capital but has led militants to increase their attacks outside Baghdad.

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