Navy vessels, tug boats and rescue ships were pressed into service on Tuesday to evacuate over 500 people stuck on an oil rig and barges in the high sea off the Mumbai coast after a cyclone Tauktae ripped through it.
The cyclone sank a barge that had living quarters for employees working offshore, while two other construction barges lost anchors and drifted away.
The three barges, which were deployed by Afcons for a contract the company had got from ONGC, had 599 workers on board when the cyclone hit, official sources said.
Besides the barges, one drilling rig of ONGC, 'Sagar Bhushan', with 101 people on board (37 ONGC employees and 64 contractual workers), too drifted away from its location.
Indian Navy ships - INS Kochi and INS Kolkata, Coast Guard vessel ICG Samarth, tug boat of Afcons and offshore supply vessels of ONGC have been pressed into service to rescue those stranded on the barges and the rig.
Out of 261 people on Barge 'Papaa-305' - the worst hit by the cyclone and high sea swell - 182 have so far been rescued, they said.
Attempts are being made to trace and rescue the remaining, they said.
All the 137 persons onboard barge 'Gal Constructor', which runs aground about 48 nautical miles north of Mumbai's Colaba Point, are safe and in the process of being evacuated.
Barge 'Support Station-3' had 201 persons and is drifting North-West but is clear of all operational installations of Mumbai High - India's biggest oilfield.
Operations to bring these persons to safety are on.
Rescue vessels including 'ICGS Shoor' of Coast Guard have reached ONGC's drillship 'Sagar Bhushan', which lost its anchors and started drifting north, sources said.
Cyclone Tauktae made landfall on Monday night on the Gujarat coast, which is dotted with oil and gas installations.
While the offshore has fields producing oil and gas, the coast houses two big refineries and some of the busiest ports.
The cyclone, whose intensity is similar to the one that hit Gujarat in 1998, has weakened but heavy rain is likely to continue in parts of Gujarat, with wind speeds reaching as high as 125 kilometers per hour, according to the meteorological department.
ONGC has rushed its director in-charge of offshore operations, Rajesh Kumar Srivastava to Mumbai to coordinate the rescue operations with ODAG (Offshore Defence Advisory Group) and MRCC (Maritime Rescue Coordination Centre).
Sources said ONGC had in preparation for the cyclone moved away a floating oil production unit, called FPSO from its Panna field in western offshore.
The FPSO will be back in its place in a couple of days.
Production from only the Panna field was impacted because of the cyclone and operations on other fields including giants Mumbai High and Bassein continue as normal, they said.