Russian ships trapped in ice prison

Approximately 500 seamen remain trapped aboard ships caught in ice in Russia's Northern Pacific, waiting for icebreakers to free an escape passage in the Sea of Okhotsk.

The Russian transportation ministry initially sent the icebreaker Magadan, which does not have enough power to free the ships alone, so ministers dispatched icebreaker Admiral Makarov to crack through the two-metre-thick ice.

Three ships became stuck 11 miles from the coast of the Khabarovsk Territory on Thursday: a fishing vessel, a refrigerated freighter, The Bereg Nadezhdy, and the scientific research ship Professor Kizevetter.

Admiral Makarov Captain Gennady Antokhin gave an update to shipping officials by telephone, painting a picture of a frozen, slow process in reaching the ships.

"The situation remains difficult. We have a thick layer of ice on board, and we're hardly crawling with our seven diesels," he said.

Officials said they would have a brief window to complete the freeing of the ships.

The State Marine Rescue Centre told Itar-Tass that the crews have sufficient food and water supplies and are not in danger.

In winter, the Sakhalin Bay is considered one of the most dangerous maritime regions of the Okhotsk Sea with few clear water gaps on its surface. Mariners risk the conditions to net huge profits on the sea's store of herring and pollock.