Ten people were confirmed dead and several were still missing Thursday from a massive fire on an oil platform in India’s biggest oil field. Ships and helicopters rescued more than 350 survivors.

The government said it would take a month to recover most of the lost oil production. The state-run Oil and Natural Gas Corp., which owns the platform, said it had started cleaning up an oil spill that stretched up to 10 nautical miles.

The fire on the platform 100 miles off the financial hub of Bombay was brought under control late Wednesday after a dramatic rescue and firefighting mission in rough waters.

The fire coincided with the worst monsoon rains in decades, which left more than 500 dead this week in Bombay and the surrounding state.

Vice Adm. Madanjeet Singh said 10 people had died and several were missing. Six divers were still trapped in a support vessel.

“We have managed to rescue 367 people,” Singh said.

Navy ships and helicopters carried survivors and bodies of the dead oil workers to Bombay on Thursday. Some survivors were being treated for burns.