1.952968-3084188630
The "Kolskaya" oil drilling rig is pictured in the Kola Bay near Russia's northern seaport of Murmansk in this November 27, 2010 file photo. Image Credit: Reuters

Vladivostok: At least two people died and 51 were missing in freezing water after an oil rig in Russia's Far Eastern Okhotsk Sea overturned on Sunday, officials said as rescue efforts halted for the night.

The Kolskoye oil rig platform with 67 on board was 200 kilometres from the shore when the accident occurred at 0145 GMT amid high winds and temperatures of minus 17 degrees Celsius.

"We could rescue 14 people out of 67," regional ministry spokesman Taimuraz Kasayev said. "Two more bodies without signs of life were found, but we were unable to lift them out of the water yet." Two of those rescued are in critical condition, he said.

The platform was fully submerged by evening, and all four life rafts had been found with no people on them.

Rescue efforts were complicated by high winds and waves up to five metres high. The platform was being towed by a tugboat and icebreaker from the Kamchatka peninsula towards Sakhalin island.

"The portholes were damaged by ice and waves, and water began going into the vessel," Kasayev said. The crew was waiting to be evacuated by helicopter but the platform turned over and sank before they could board their rescue rafts, he said.

The Kolskoye platform had problems even before the accident, and was forced to constantly pump water out of one of its air tanks due to a leak, he said.

Helicopters participating in the rescue were sent to shore with four of the victims, he said. By then the missing had spent more than six hours in the freezing waters without life rafts.

Officials did not say whether there was any hope of finding any of the victims alive. They may be wearing wetsuits and life vests that were aboard the rig.

The Kolskoye rig was engaged in shelf exploration in western Kamchatka peninsula for Gazflot company, a subsidiary of Russia's gas monopoly Gazprom. The risk of an oil spill from the platform is "minimal", Kesayev said. "The fuel is in air-sealed tanks, so there is no risk of a spill."

"The investigation's main suspected reason for the accident was a violation of safety regulations by transporting the platform without taking account of weather conditions, as there was a strong storm in the area," investigators said in a statement.

The potential death toll of 53 comes five months after 122 people drowned in the Volga river when the overcrowded pleasure boat Bulgaria sank in the Tatarstan region after turning over in stormy weather.