At least six passengers were killed when a local state transport bus collided head-on with an oncoming truck on the Ausa-Nilanga state highway on Saturday, an official said.According to the Latur Police Control, the accident occurred at 3.00 p.m. near the Chalburga Phata, around 30 km from here.A speeding truck rammed into the jampacked bus -- carrying 71 passengers from Latur to Nilanga -- tearing off the metal body of the bus from the driver's seat to several rows behind him on the right-hand side.While at least six persons, including two women, were killed instantly, another 35 were reported to be injured and were rushed to the Latur Civil Hospital and other hospitals in Ausa village.The cause of the accident is not clear yet. Local authorities fear the number of fatalities may increase as several injured, including the bus driver and the conductor, are critical.