Balotra, Feb. 28 -- Six people died on the spot and several were left critically injured after a sleeper bus collided with a trailer on a stretch of the National Highway-25 near Sarwadi village in Balotra district on Friday, police said. The incident occurred after the bus, which was allegedly speeding, switched lanes to overtake two vehicles and hit the trailer, which was approaching from the opposite side, said Balotra superintendent of police Ramesh, adding that the impact was so severe that the driver's side of the bus was completely crushed. The bus was travelling from Jodhpur to Sanchore near the Gujarat border, and the trailer was travelling to Jodhpur, he added. Those injured were sent to nearby hospitals for treatment, said officials, adding that some were referred to better facilities owing to their critical condition. Police have registered a case, they said. Preliminary investigations suggest that speeding and negligence may have contributed to the accident, said the SP, adding that the exact cause was under investigation....