Two cargo ships have collided in the Baltic Sea between the Danish island of Bornholm and the southern Swedish city of Ystad, Swedish media reported on Monday, citing the Swedish Maritime Administration.
One ship was registered in Denmark, and the other was British, Sweden's public broadcaster SVT said on its website.
"One of them is upside down. We don't know exactly how it happened," SVT quoted Swedish Maritime Administration spokesperson Jonas Franzen as saying.
"The Danish ship had at least two persons on board," Franzen said.
A big rescue operation was underway, SVT said.
Swedish news agency TT cited a Swedish coastguard spokesman saying one of the vessels was 90 metres long, and the other was 55 metres.


Damascus cafe blast kills 5, wounds 16
Russian air strikes kill 10, injure more than 50 in Ukraine's Kyiv
Firefighters battle wildfire in southern France
US, Iran talks conclude in Doha, focused on Strait of Hormuz
Trump honours Theodore Roosevelt in North Dakota, debuts new Air Force One
Kenyan court charges 8 schoolgirls with fellow students' murder
At least 5 people killed in fire in Antwerp apartment block
Three people die in Mexico World Cup celebrations as fans crowd streets
