Four persons, including three Oil and Natural Gas Corporation (ONGC) employees, died when a Pawan Hans helicopter with nine people onboard fell into the Arabian Sea off the coast of Mumbai on Tuesday.
The nine people included two pilots and seven passengers. The incident took place 50 nautical miles from the Mumbai coast.
The helicopter managed to stay afloat with the help of the attached floaters for some time, helping rescuers pull out all the nine people, according to an ONGC official.
He added that four of them were unconscious and were airlifted in an Indian Navy helicopter to a hospital in Mumbai, where they were declared dead.
PTI earlier reported that the helicopter was attempting to land at ONGC rig Sagar Kiran, some 50 nautical miles from the Mumbai coast, when the incident took place. The helicopter is said to be a brand new Sikorsky helicopter that Pawan Hans had recently taken on lease.
About 1.5 km from the landing zone on the rig, the helicopter went into the sea but not before it fully inflated its floaters that helped it to stay afloat, according to an official.
The circumstances that led to the incident were not immediately known.
ONGC has key oil and gas fields off the Mumbai coast and Pawan Hans helicopters routinely ferry company employees and officers to the oil installations that are situated as far as 160 kilometers from the coastline. These offshore fields include Mumbai High, the nation's largest oil field, and Bassein fields, the largest gas field.
(With PTI inputs)