Kathmandu, 2 February : At least four passengers have died and eight others are seriously injured in a road accident that occurred at the wee hours of Sunday. Three persons were killed on the spot when a bus and a microbus collided head-on at Titriban of the district while another succumbed while undergoing treatment at the BP Koirala Institute of Health Sciences,  (BPKIHS)Dharan. According to Sunsari District Police,  Hem Raj Koirala of Kathmandu and microbus driver Deepak Khadka's died on the spot.  The identification of two others killed is yet to be ascertained. The injured were rushed to BPKIHS for treatment.   People's News Monitoring Service