(CNN) -- Search and rescue efforts have been scaled back for 17 men missing since a South Korean fishing vessel sank Monday in the frigid Southern Ocean waters of Antarctica, a New Zealand rescue agency said.
"As time passes the chances of any of the remaining crew surviving are increasingly slim," the Rescue Coordination Centre in New Zealand said.
Two vessels have already been released from the search team, according to Maritime New Zealand, a government agency which monitors the ships and waters of coastal New Zealand. The rescue team said it will "re-evaluate the situation," and make a decision about continuing the search in the morning.
The ship sank about 6:30 a.m. (12:30 p.m. ET Sunday) in a remote swatch of the Antarctic Ocean some 1,850 km (1,150 miles) north of McMurdo, a U.S. research center on the tip of Ross Island. Maritime New Zealand learned of the incident around 1 p.m., some 4 1/2 hours later.
The New Zealand agency and the Korea Coast Guard said that five people died, 20 were rescued and 17 were missing. CNN
