Two men were out fishing early Sunday morning when a wave crashed over their boat, which keeled over and left the men in the chilly water.
The rescue mission began at eight am, when one of the men managed to reach the shores of the island of Nordkoster on Sweden's west coast on his own after some five hours in the water, and managed to alert the authorities of the accident.
“He's doing relatively well. Swimming for five hours in these temperatures is pretty good,” said assistant rescue leader Christer Ekeroth of the Swedish Maritime Administration (Sjöfartsverket) to the Aftonbladet newspaper.
The other man is still missing, despite the three boats and two helicopters that have been searching for him for hours.
According to the rescue operations, certain finds have been made in the water, including two paddles.
The search team hopes that the man has managed to reach shore somewhere, pointing out that time and the cold water are against him.
“If he's on an island somewhere, things are looking good,” Ekeroth said to Aftonbladet.
The missing man and his companion are both in their mid-twenties and come from Norway, according to the rescue operations.