TORONTO (Reuters) - Rescuers combed the frigid waters off Canada's Atlantic Coast on Thursday looking for survivors after a helicopter carrying 18 people crashed as it ferried workers to two offshore oil facilities.

One person has been rescued after the crash off the coast of Newfoundland, said Rick Burt, general manger of Cougar Helicopters, which operated the Sikorsky S-92 transport.

CBC television reported that one person had been found dead, while 16 were still missing.

Two life rafts also have been pulled from the water, but nobody was in them, rescuers said.

The helicopter sank in the North Atlantic about 40 miles southeast of the Newfoundland and Labrador capital of St. John's, leaving behind a debris field.

It was carrying 16 passengers and two crew and was heading for the Sea Rose production vessel and the Hibernia oil platform when it sent out a distress call at 9:18 a.m. local time (1148 GMT). Hibernia is about 315 kilometers southeast of St. John's, and Sea Rose is about 35 kilometers farther away.

The pilot did report that he was having some technical malfunction and was turning back to St. John's, Burt told a press conference.

He had no information on the survivor's condition.

Hercules aircraft, Cormorant helicopters and surface ships were in the area trying to find survivors in the near-freezing water, said Denis McGuire of the Joint Rescue Coordination Center in Halifax, Nova Scotia.

The search effort is going on right now, he said.

Cougar equips passengers on its helicopters with survival suits that can sustain life for up to 30 hours in such a situation, according to the company's website.

Television images showed a Cougar helicopter arriving at a helipad in St. John's with the survivor on a stretcher.

Rescuers said water temperatures were just above freezing, with waves of up to three meters (nine feet), winds in the 25-35 knot (46-65 km/h) range and good visibility.

Fourteen of the passengers had been heading to the Sea Rose vessel, which is operated by Husky Energy, while two were traveling to Hibernia.

The Hibernia platform is owned by Petro-Canada, Exxon Mobil Corp. with 33.125 percent, Chevron Corp., Murphy Oil Corp. with 6.5 percent, StatoilHydro, and the government of Canada.

(Reporting by Cameron French; Editing by Peter Galloway)