One person has been rescued, another died and 16 were missing on Thursday after a helicopter ferrying workers to an offshore oil rig crashed into the icy North Atlantic Ocean off Canada's east coast.
The downed helicopter was flying from Saint John's, Newfoundland, to the Hibernia offshore oil platform when it plunged into the ocean some 87 kilometers (54 miles) southeast of Saint John's at 9:18 am (1148 GMT), said officials.
One person was plucked from the frigid waters and rushed to a hospital in Saint John's, and a body was recovered hours after the crash.
Prime Minister Stephen Harper described the downing in the House of Commons as a "tragic accident" and vowed search and rescue teams would continue an "intensive search" for the other 16 passengers and crew.
Earlier, two life rafts were found floating among the debris, but there was nobody onboard, a spokewoman for the Joint Rescue Coordination Center in Halifax, told AFP.
They may have been deployed manually or automatically inflated when the helicopter hit the water, officials said.
"The aircraft has sunk," Rick Burt of charter firm Cougar Helicopters told a press conference. But "we are hopeful and so we'll continue to search until there's no hope whatsoever," he said.
"The aircraft was on its way out, experienced technical problems, radioed in that it was turning around and that was the last that we had communication," he said.
The chopper was part of Cougar Helicopter's newer fleet of Sikorsky S-92 helicopter and weather at the time of the accident was mild.
As rescuers continued to comb the area, however, winds picked up creating waves up to three meters (nine feet) high, and water temperatures were near freezing (0 Celsius, 32 Fahrenheit), officials said.
"We identify search patterns that we use that ensure that the entire area is covered and we do a drift assessment to determine where anything on the surface would have drifted," Burt said.
He said the missing passengers could last up to 24 hours in the water, wearing survival gear.
A half dozen military and civilian aircraft and Canadian Coast Guard vessels were despatched to scour the area.
At the onset, a military plane on a routine training mission and a merchant ship were first on the scene. Others took up to an hour to reach the crash site.
The lone survivor so far was picked up by a civilian helicopter owned by Cougar Helicopter.
Since then, the company said it has temporarily suspended all of its offshore flights until it knows the cause of the crash.