Nine people were killed and six others injured in a traffic accident in Arghakhanchi district of western Nepal on Sunday, police said.A jeep skidded off the mountain road at Hansapur area of the district and plunged into a local river, killing nine people on the spot, police officer Kulchandra Pokharel told local media.The over-loaded passenger jeep was en route to Bandikot area of Pyuthan district from Sandhikharka, the headquarters of Arghakhanchi district, when it slipped off the highway, witnesses told local media.The accident was the third deadly one in the Himalayan nation in three weeks. On August 26, 22 people were killed and 17 others injured in a bus accident in Chitwan district of central Nepal.The poor condition of hilly roads and ill-maintained vehicles are said to be the reasons behind frequent road mishaps in Nepal.