An Oil and Natural Gas Corporation (ONGC) helicopter with nine people on board made an emergency landing near an oil rig in the Arabian Sea on Tuesday. Six people have been rescued so far, ONGC said. The helicopter mishap occurred around 11:50 am, about 60 nautical miles west of Mumbai, near ONGC’s Sagar Kiran offshore rig. A total of nine people, including seven passengers and two pilots, were on board the chopper.