N'Djamina - Amnesty International said the detention of 84 children, for several months in Cameroon, has highlighted concern that the regional campaign against Islamist group, Boko Haram, was leading to rights abuses.
The report came as the Republic of Niger's National Commission for Human Rights (CNDH) denounced a wave of arbitrary detentions under a four-month-old state of emergency to fight Boko Haram.
He commission is a state body made up of lawmakers, civil society figures, magistrates, lawyers and union leaders.
Steve Cockburn, Amnesty's Deputy Regional Director, on Wednesday in N'Djamina called for the immediate release of the children.
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"Some detainees, some as young as five years old, have been tortured to death within the eight months.
He said the children were detained by security forces in a raid in December, on Islamic schools in Cameroon's Far North Region, which authorities said were Boko Haram training camps.
The Chad Basin countries' joint offensive has liberated large swathes of territory from Boko Haram, which has killed thousands of civilians in a six-year campaign to carve out an Islamic state.
"There is a real risk of human rights violations in all of the countries threatened by Boko Haram.
"The countries that are also threatened by Boko Haram do not have to repeat the same mistakes and the same errors as Nigeria,” Cockburn said.
He said in Cameroon, there was documentation of a rise in arbitra