New Delhi, July 19 -- The Aircraft Accident Investigation Bureau (AAIB) on Saturday released the preliminary report into the May 8 Uttarkashi helicopter crash which claimed the lives of six people including the pilot.

The report said that the helicopter crash near Gangnani in Uttarkashi was caused during emergency landing by the main rotor blade striking an overhead fibre optic cable.

The report said that 20 minutes after takeoff, the helicopter began to descend from its assigned altitude.

One passenger survived but sustained serious injuries. The crash occurred around 08:35 am during a chartered Char Dham Yatra flight.

The Bell 407 helicopter, registered as VT-OXF and operated by Aerotrans Services Pvt. Ltd., had departed from Kharsa...