Six people have been injured in a collision between a crew transfer vessel and a Polish cargo ship off Germany.

Casualties were airlifted from the high-speed crewvessel World Bora this morning after it came into contact with Baltramp Shipping’s 2,300-dwt Raba (built 1984).

A spokesperson for windfarm operator Iberdrola told TradeWinds' sister publication Recharge that four crew members and two technicians were now receiving medical treatment.

The nature of their injuries is unclear.

Pictures from German authorities show the Raba had been damaged in the incident.

A spokesperson for the Baltramp told TradeWinds the company was concerned about the injured parties but confirmed nobody had been harmed onboard its own vessel.

After inspections have been carried out, it is expected the Raba will return to Poland for repairs, he said.

It is not yet clear what caused the accident seven nautical miles off the island of Rugen.