Russian air and sea rescue teams were searching on Monday for dozens of people missing after a Pacific coast oil rig sank, killing at least 16 people, officials at the Emergency Situations Ministry said.
Ships, helicopters and fixed wing aircraft were battling foul weather and freezing temperatures in the Sea of Okhotsk, some 7,000 kilometres east of the Russian capital Moscow, DPA reported.
A total 67 people were reportedly aboard the platform when the rig sank in a storm on Sunday. It had been under tow by an icebreaker some 200 kilometres to the East of Russia's Sakhalin Island.
Fourteen workers had reached safety by Monday morning, the Interfax news agency reported. A storm warning was in effect with waves exceeding five metres.
The rig went underwater in less than 20 minutes, possibly because accumulated ice prevented water-tight hatches from closing, news reports said.
A government investigation into the accident was in progress, a statement from Russia's Attorney General's office said.