Emergency services said they stopped looking for a missing Swedish crew member because he was likely dead after more than 12 hours in the frigid waters of the Baltic.
The other sailor, a Filipino national, died in hospital overnight from injuries sustained after the Swedish-registered Finnbirch sank on Wednesday between the islands of Öland and Gotland.
High seas and wind hampered the rescue efforts of helicopters that airlifted 13 of the Finnbirch’s 14 Swedish and Filipino crew from the capsized 155-metre ship.
The Swedish coast guard said the container ship was carrying some 250 tonnes of heavy oil and 10 tonnes of machine oil when it went down.
A German military aircraft is due to assess the extent of the oil spill, but according to experts some of the oil has already leaked.