Ten generals and five other senior military officers have been found guilty in a court-martial of providing arms and information to Boko Haram, several Nigerian newspapers reported, though the military denied the accusations.
The developments, first reported on Tuesday, follow months of allegations from politicians and soldiers who told The Associated Press that some senior officers have been helping the armed group, and that some rank-and-file soldiers even fight alongside the rebels before returning to army barracks.
Nigeria's government and military have come under increasing scrutiny for failing to find hundreds of schoolgirls kidnapped in April by the armed group, which wants to carve out a fundamentalist Islamic state in northern Nigeria.
Sources have said that information provided by army officers has helped Boko Haram to ambush military convoys, and in attacks on army camps and outposts in the militant group’s northeastern stronghold.
The Leadership newspaper quoted one officer as saying that four other officers, in addition to the 15, were found guilty of "being disloyal and working for the members of the sect [Boko Haram].”
Defense Ministry spokesman Maj. Gen. Chris Olukolade, who last week denied reports that senior officers were being investigated, reiterated in a statement Tuesday that defense headquarters "wishes to state once again categorically that there is no truth whatsoever in the report.”
He called it a "falsehood" concocted by those who "appear hell-bent on misleading Nigerians and the international community to give credence to the negative impression they are so keen to propagate about the Nigerian military.”
The Defense Ministry's statement was contradicted when Interior Minister Abba Moro told the BBC Wednesday that the courts-martial were "good news.”
The Nigerian military is accused of such gross human rights violations that Washington's efforts to help in the rescue of the nearly 300 abducted schoolgirls have been limited by U.S. law restricting the sharing of some types of information and technology with abusive security forces.
The alleged sabotage by senior officers could explain the military's failure to curb a five-year uprising by Boko Haram that has killed thousands despite a yearlong state of emergency in the northeast.
President Goodluck Jonathan said last year he believed that some members of the military, and even of his own government, including some Cabinet ministers, sympathized with Boko Haram or belonged to the group.
Jonathan in January fired his entire military command and weeks later replaced the defense minister.
Al Jazeera and wire services