DUBAI, May 31 (Reuters) - An Iraqi al Qaeda-led group said one of its fighters carried out a suicide bombing in Falluja which killed up to 20 men queuing at a police recruitment centre on Thursday.

Falluja police spokesman Hamid Abid said the bomber, wearing a suicide explosives vest, walked up to a queue of about 150 young men at a police recruitment centre and blew himself up.

But the group, the Islamic State in Iraq, said he used a car bomb.

"A brave knight, a hero of the Islamic States in Iraq ... drove his car bomb into a recruitment centre of the apostate police in Falluja," it said in a statement posted on a Web site used by insurgents.

Falluja, 50 km (35 miles) west of Baghdad, is in restive Anbar province, a stronghold of the Sunni Arab insurgency.

Recruitment centres for Iraqi security forces are common targets for such attacks, which are mostly blamed on Sunni Islamist al Qaeda.

The U.S. military has more than 6,000 troops in Anbar, where local commanders have said al Qaeda accounts for about 75 percent of militants in and around Falluja.

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