The alarm came shortly after 11 p.m., when police and ambulances were called to the Western Harbour in Malmö.
The incident is being investigated as murder, but police do not want to say whether any suspects have been arrested.
The police cordoned off a large area and used drones in their work at the scene. The cordons are still in place, but the area has been reduced.
"During the night we are working on questioning witnesses in the area and conducting door-to-door inquiries. We have technicians on site and the police will remain for several more hours," says Peter Martin.
The police are currently unable to say whether the deceased was previously known to police.
