Preliminary data based on the notification from the authorities of Ghana :
During take off roll and before the aircraft gathered speed to reach 70 kt, the Captains's seat suddenly moved full backwards violently and shifted to the left. Whilst controlling the aircraft with the nose wheel steering, the violent seat movement led to the captain turning the tiller to the left causing the aircraft to veer off/excurt the runway. The Captain could not gain control of the aircraft until it came to a stop close to the perimeter fence after efforts by the copilot to retard the power levers. After procedures to secure the aircraft was performed, the passengers were disembarked with five injured.