Human Rights Watch has accused Nigerian officials of sexually exploiting women and girls living in camps for victims of Boko Haram in the war-torn northeast.
HRW said in July it documented 43 cases of women and girls in seven internally displaced persons' (IDP) camps in Maiduguri, the epicentre of the seven-year Islamist insurgency, who had been abused by camp leaders, policemen, and soldiers.
"It is bad enough that these women and girls are not getting much-needed support for the horrific trauma they suffered at the hands of Boko Haram," said Mausi Segun, senior Nigeria researcher at HRW. "It is disgraceful and outrageous that people who should protect these women and girls are attacking and abusing them."
Nigerian President Muhammadu Buhari said he was "worried and shocked" by the report and directed police to "immediately commence investigations into the issue".
Four of the victims told HRW they were drugged and raped, while 37 were coerced into sex through false marriage promises and material and financial assistance."The welfare of these most vulnerable of Nigerian citizens has been a priority of his Government," presidency spokesman Garba Shehu said, adding that the allegations raised by Human Rights Watch "are not being taken lightly".
"Many of those coerced into sex said they were abandoned if they became pregnant. They and their children have suffered discrimination, abuse, and stigmatisation from other camp residents," the global rights body said.
Boko Haram has devastated northeast Nigeria in its quest to create an Islamist state, killing more than 20,000 people and displacing 2.6 million from their homes.
But since 2009 when the insurgency started, the Nigerian military has also come under fire from international rights groups.
Amnesty International has alleged that the Nigerian military "committed war crimes and possible crimes against humanity in its response to Boko Haram".
The rights group has also accused the military of deliberately shooting dead more than 350 Shia Muslims in December last year.