Two sailors were missing on Monday after falling into the frigid waters of the Baltic Sea south of Sweden when two cargo ships collided in the early morning hours, officials said.
Nine boats and a rescue helicopter were scouring the waters for the sailors following the collision between the Swedish city of Ystad and the Danish island of Bornholm, the head of press at the Swedish Maritime Administration was quoted as saying by AFP.
"Shortly after half past 3 am (0230GMT), we received an alert through our sea and flight rescue central that two freight vessels have collided," Carl-Johan Linde said.
"One of the ships has capsized and is upside down," Linde said, adding that two people from that vessel fell into the water as a result of the collision.
The British flagged Scot Carrier was headed for the Swedish island of Gotland, while the Danish flagged Karin Hoej, which capsized, was headed for Denmark, according to Linde.
"The Scot Carrier released a smaller boat and looked for people and they heard screams from the water, but couldn't find anyone," Jonas Franzen, communications director at the Swedish Maritime Administration, told AFP.
Soren Hoj, manager for the Danish shipping company operating the Danish-flagged vessel, told AFP that there were two people in the crew and they were believed to be the ones missing.
Sweden's Coast Guard said they had multiple vessels assisting the rescue operation and that around 9 am a tow line had been attached to the capsized ship so that it could be towed to shallower waters.
"This is to avoid a shipwreck and enable divers to search for missing crew members," the Coast Guard said in a statement.
Operations to prevent oil or other hazardous materials from being released into the water were also under way.
"There is currently no ongoing oil spill," the coast guard said in a statement.
Prosecutors have opened an investigation into "gross negligence in sea traffic," the coast guard said.
The waters around Sweden's southern coast see heavy traffic, as all ships going into the Baltic Sea from the Atlantic need to pass through the strait between Sweden and Denmark.