At least four passengers were killed and eight injured when the Delhi-Dibrugarh Rajdhani Express derailed at Golden Ganj station near Chapra early today. Five coaches - B-1, B-2, B-3, B-4 and pantry car - overturned as a result of the derailment, while seven other coaches - B-5 to B-10 and power car - got derailed near the station. The police have ruled out the hand of Maoists in this incident.