A BN-2T Islander was engaged in transporting a total 627 kg of cargo, which included two drums of Jet A-1 fuel, from Port Moresby to Kikori, Papua New Guinea. The flight to Kikori was uneventful. The pilot stated that he joined the Kikori circuit upwind for a left downwind and, after completing the pre-landing checks, set up for a landing on runway 30. The pilot reported that, after touchdown, he held the nose wheel off the ground. He stated that the initial landing and roll-through on the steel matting surface were normal. When applying brakes, the aircraft veered left and ran off the runway. The aircraft subsequently impacted an embankment beyond the left side of the runway, approximately 70 metres from the runway end. The nose of the aircraft was crushed and the nose landing gear partially collapsed rearwards during the impact with the embankment. Two of the left propeller blades were bent. Based on the differences between the pilot’s statements and the statement by the witness, the AIC was unable to ascertain the exact touchdown point. Prior to the accident flight, the aircraft had undergone a 100-hourly maintenance check at Port Moresby performed by the operator’s maintenance provider. The AIC was informed that during this check the brake pads had been changed and the brake system had been bled and refilled with hydraulic fluid. The AIC’s on-site investigation of the brake system did not reveal any defects in the system, however, the aircraft had been moved after the accident by the operator’s personnel and the AIC was unable to determine to what extent the condition of the aircraft and its systems had changed in the time between the accident and the AIC’s arrival at Kikori. The final report did not contain a Probable Cause statement.