An allegation that Iraqi police raped a Sunni woman while enforcing a new security plan in Baghdad has opened sectarian splits within the government
The woman said she was assaulted at a police garrison on Sunday where she was falsely held for supporting insurgents.
Prime Minister Nouri Maliki, who is Shia, dismissed the claims, but senior Sunni officials insist it is true.
Observers say the row could undermine the security plan, in which mainly-Shia police are deployed in Sunni areas.
Mr Maliki accused "known groups" - taken to mean Sunni political parties - of fabricating the story, to discredit the security forces.
A series of insurgency attacks in and around the capital have already shown the difficulties of trying to stem the tide of violence.
Sunni and Shia: Spectre of sectarianism
Was There Rape? Depends on Whether You're Shiite or Sunni