The Nigerian government is failing to prosecute police and soldiers who rape women and girls with impunity, says rights group Amnesty International
The country's police authorities acknowledge rape is a problem within the service, but say that they are working to overcome it.
An AI report alleges security forces use rape and sexual violence to torture and extract confessions from suspects.
It blames the judicial system for a 10% rape prosecution success rate.
The report calls for drastic reforms of the judiciary and security agencies.
"The perpetrators invariably escape punishment, and women and girls who have been raped are denied any form of redress for the serious crimes against them," the report says.
It also documents cases of soldiers raping mothers in front of their husbands and children and detainees being sexually tortured with broken bottles.
"The harsh reality is that if you are a woman or a girl in Nigeria who has suffered the terrible experience of being raped, your suffering is likely to be met with intimidation by the police, indifference from the state and the knowledge that the perpetrator is unlikely to ever face justice," said Kolawole Olaniyan, Africa Director of Amnesty International.
Although Nigerian law stipulates life sentence - or death by stoning under Sharia law in the predominantly Muslim north - the report says most rape cases in Nigeria go unreported because the victims fear they would be rejected by the community.
The victims also fear that the soldiers and policemen who raped them in the first place might hurt them again if they reported the crime.
One report cited the case of two teenage students it said were kidnapped and gang-raped by three policemen for several hours in Enugu State in 2004.
There has been no judgment yet from the Nigerian courts on the case and the victims and their families said they have received death threats.
Another case cited in the report was that of another woman who was raped along with her mother and daughter.
"The armed people held my mother, they raped her ... they raped me. I was two months pregnant and I had a miscarriage," she said.
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