About a dozen killer whales trapped under sea ice appear to have swum free after the ice shifted, village officials in Canada's remote north have said.
However, residents who feared they would get stuck elsewhere hired a plane to track them down.
The whales' predicament in the frigid waters of Hudson Bay made international headlines, and locals had been planning a rescue operation with chainsaws and drills before the mammals slipped away.
Tommy Palliser said two hunters from remote Inukjuak village reported that the waters had opened up around the area where the cornered whales had been bobbing frantically for air around a single, truck-sized hole in the ice. Officials said shifting winds might have pushed the ice away.
"It's certainly good news - that's good news for the whales," said Mr Palliser, a business adviser with the regional government.
But fears remained that the whales might have been trapped elsewhere by the ever-moving ice.
Inukjuak, about 930 miles north of Montreal, hired a plane to scan the region for signs of the whales, town manager Johnny Williams said.
"We're quite concerned, that's why we're chartering the plane to find out if we can find them," Mr Williams said, adding that the village of 1,800 will probably pay for the aerial search.
Locals said the whales had been trapped for at least two days. A recent, sudden drop in temperature may have caught them off guard, leaving them trapped. They were first seen on Tuesday and appeared to have less energy by late on Wednesday, Mr Palliser said.
The Department of Fisheries and Oceans issued a statement saying that two scientists were en route to gather information and will monitor the situation. Ice-trapped marine mammals are not unusual in the region.