The Association of Muslim Scholars, a leading Sunni group, says the men were detained by the police a week ago while they were praying at a mosque.
Sunni Arabs frequently accuse the Shi'ite-led security forces and militias of kidnapping and killing ordinary Sunnis and clerics.
The Interior Ministry said it could not confirm that the men had been in police detention but said that an investigation is under way.
It also reported that one Iraqi man had been killed and four wounded, including two policemen, in separate attacks across Iraq early on 4 February.
RFE/RL Iraq Report
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