Six other passengers in the vehicle were injured and taken to hospital, a fire department spokesman told dpa. He could not provide any information about their condition.

“It is a very, very terrible accident,” a Koblenz police spokesman said.

The cause of the accident is still unclear and the identities of some of the people in the minibus have yet to be confirmed. The spokesman said foreign nationals were among the victims.

Initial findings indicated that the minibus had veered off A48 motorway and overturned. No other vehicle was involved. However, another vehicle drove over debris shortly after the accident.

The motorway was closed, with traffic diverted, police said.