VLADIVOSTOK - The Atlas rescue vessel has joined the searching of the missing crewmen Monday morning after the overturn of Russia's Kolskaya drilling rig on Dec 18, the Itar-Tass News Agency said.

The Atlas vessel is working with other rescuing boats, including the Magadan icebreaker, the Georgy Froyer tanker, and the Smith Sakhalin supply vessel.

Meanwhile, three helicopters and two airplanes are also helping search the missing men in the surrounding areas.

Up till now, four have been confirmed dead and 14 others rescued, leaving 49 missing.

The authorities had confirmed that the poor weather condition and freezing water are both diminishing hopes for finding those missing alive.

Russia's Transportation Ministry said earlier that strong waves broke some of the rig's equipment and the portholes in the crew's dining room, which caused the rig to capsize some 200 km off Russia's Far East Sea of Okhotsk at 4 pm local time (05:00 GMT) on Dec 18.

And the life boats were also washed away by waves, leaving the crew with no chances to escape.

No immediate environmental pollution has been so far reported.