Mumbai, June 25 -- A mere 0.75-metre gap between commuters hanging by the footboard on two suburban trains running in opposite directions at 75 kmph-a relative speed of 150kmph-and the track curvature that caused the trains to oscillate sideways led to eight commuters falling on the railway tracks in Mumbra on June 9, of which five died. These are the preliminary findings of a five-member inquiry committee set up by Central Railway (CR) to investigate the incident, according to officials. The entire incident, which occurred in a matter of seconds, is likely to have been sparked by a commuter on the Chhatrapati Shivaji Maharaj Terminus (CSMT)-Karjat fast local falling off the footboard, the reason for which is still unknown, officials added. "Prima facie, it seems that the hand of the said commuter, who was carrying a shoulder bag, was hanging outside the coach since he was on the footboard," said a CR official, requesting anonymity. "It seems that as the train was passing Mumbra, he somehow fell from the footboard, taking another passenger-a GRP (Government Railway Police) cop-standing behind him down with him. There is no understanding on how he fell." Before he fell, the man with the shoulder bag was apparently flung onto the adjacent CSMT-bound fast local and hit a few passengers standing on the footboard of that train, the official said. Six passengers from the Kasara-CSMT local fell on the tracks. "The entire episode unfolded in a matter of a second or two," said the official, adding that the bag of the commuter on the Karjat-bound train left a black gash on one of the coaches of the Kasara-CSMT local. The distance of 0.75 metres between commuters on the two crossing trains assumes significance, said officials, since the distance between the coaches was 1.8-2 metres, which is as per norms. While the Kasara-CSMT fast local was overcrowded with office-going commuters during the morning rush hour, the Karjat-bound train was not packed, officials said. Over two weeks since the incident, which also left nine commuters injured, CR authorities are finding it hard to piece together the series of events, including the reason behind the man with the shoulder bag falling off the footboard. CCTV cameras installed at the Mumbra station, where the collision occurred, shows the two trains but does not cover the portion at the centre of the two rail lines where commuters fell off. The inquiry committee, consisting of senior CR officers from the security, safety, operations, engineering and electrical departments, will submit a final report within a week....