The Nigerian Army Headquarters says a depressed soldier serving in 2 Battalion of 21 Special Armoured Brigade, Bama, Borno State, went berserk, shot and killed an officer on Wednesday.
The Acting Director, Army Public Relations, Sagir Musa, disclosed this in a statement on Thursday in Abuja.
Mr Musa, a colonel, said the incident occurred when the soldier approached the officer who was standing in front of the Unit's Headquarters making a phone call.
He said the soldier is in custody undergoing investigation while the general situation in the unit remains calm.
According to the army spokesperson, the remains of the deceased officer has been evacuated to 7 Division Medical Services and Hospital.
"Investigation into the case has since been instituted to determine the circumstances that led to the unfortunate incident.
"The family of the deceased has already been contacted.
"The Nigerian Army sympathises and condoles with the family at this trying moment, and pray to the Almighty God to repose the soul of the departed and grant his family and other loved ones the fortitude to bear the irreparable loss.
"May his gentle soul rest in peace," he said.
Some 386 soldiers recently resigned their commission from the Nigerian Army citing loss of interest.