A businessman simply identified as Cletus was killed by gunmen in his office near Ekeki Motor Park, Yenagoa, on Monday.
Cletus was reportedly followed to his office early in the morning and fatally stabbed in the head.
The attackers stole an undisclosed amount of money, his mobile phone, and his Highlander jeep, which was parked nearby.
Neighbors mourned Cletus as his body was found by his employees when they arrived for work.
The businessman, aged in his late 40s, was known as a quiet figure with other business interests in the city.
The Police Command in Bayelsa, through its spokesman ASP Musa Mohammed, confirmed that an investigation into the incident is underway.