Tragedy struck in Abuja on Saturday as a police inspector, John Markus, killed his colleague and later committed suicide.
The incident which occurred very early in the morning at the Dutse Police Divisional Headquarters also left another police officer injured.
The Federal Capital Territory Police Command has released a statement condemning the incident.
The incident occurred as Mr Markus who was said to be on duty as a station guard fired a round of ammunition into the air.
He was reported to have been called to order by police corporal, Mathew Akubo, but the inspector turned to his subordinate and shot him in the head.
Thereafter, a Superintendent of Police Abdullahi Ovanu came out from the office to inquire what happened but the inspector also shot him in the arm.
A few minutes after the incident, Mr Markus shot himself through his mouth.