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BAGHDAD, July 15 (Reuters) - Two suicide bombers killed 16 police recruits and wounded 30 others at a security post north of Baghdad on Tuesday, the U.S. military said.

The attacks took place in Baquba, capital of Diyala province, where recruits were lining up. A police source said 20 people were killed and 55 wounded.

"This is an initial report and the details could change," a spokeswoman for the U.S. military in northern Iraq said.

Diyala is a volatile, ethinically-mixed province where al Qaeda militants have sought to stoke tensions and intimidate Iraqi security forces. The group has frequently targeted policemen and police recruits.

U.S. military officials say al Qaeda is trying to continue to carry out large-scale attacks to show it is still a threat, despite improving security and falling violence across Iraq.

"What's happening here is the enemy knows the government and security forces are getting stronger," the spokeswoman said. (Reporting by Tim Cocks, Editing by Dean Yates)

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