Swedish authorities have launched a rescue after a collision left a Danish cargo ship capsized and sinking.

Two seafarers are believed to be in the water and screams were heard from the site south of Ystad in the Baltic Sea.

Aftonbladet cited the Swedish Maritime Administration (SMA) as saying the 492-dwt Danish cargo ship Karin Hoj (built 1997) had turned over early on Monday after the incident involving UK owner Scotline's 4,800-dwt multipurpose Scot Carrier (built 2018).

The SMA said at around 1000 GMT it had concluded its search for the two missing crew members at the site of the collision.

Further efforts to find the crew members would resume once the capsized ship had been towed closer to land.

"We are searching intensively because we have heard screams in the water," Jonas Franzen, communications manager at the SMA, had earlier said.

Danish Defence's Joint Operations Centre (JOC) said the two missing seafarers were the only crew on the Karin Hoej.

Danish and Swedish authorities said the ships were were sailing in the same direction at the time.

The Scot Carrier has remained functional and crew members were safe.

The master of the UK ship was tested for alcohol.

About 10 vessels and helicopters from Sweden and Denmark were helping in the rescue, as well as another UK cargo ship that was nearby.

The water temperature is about 4C.

Sweden's Coast Guard said an investigation was looking into possible "gross negligence".

The JOC said there was no sign of life boats or other emergency equipment from Karin Hoj.

No cause established

"We do not know exactly what happened between the ships," Franzen added.

The Danish ship was on its way from Sodertalje to Nykobing Falster and the Scot Carrier was heading from Salacgriva in Latvia to Montrose in Scotland.

AIS data shows the Scot Carrier stopped at the scene.

The Karin Hoj is operated by Rederiet Hoj of Denmark.

"I can confirm an accident has happened but I do not know the circumstances," Hoj managing director Soren Hoj told Reuters.

The vessel was in ballast at the time.

Scotline is not commenting but is helping local authorities.

Fog was reported in the area at the time of the accident.

The JOC said: "The Danish ship, which is upside down, is a relatively small ship, so it has so little oil on board. That is not what worries us at the moment."

Neither vessel has any port state control detentions on their records.

Swedish authorities have also been dealing with a major cargo fire on an NSC Holding bulker over the past week.

The 31,800-dwt handysize Almirante Storni (built 2012) has been moved into Gothenburg so its timber cargo can be unloaded while firefighting efforts continue.

Authorities said removing the cargo would give better access to fire-hit areas.