Nineteen people have been injured after a bus en route from Belgrade to Stockholm crashed south of Berlin.

       Police said the bus swerved off the highway near the village of Sch？nwald on Friday morning, around 50 kilometres south of the capital.

       Images from the scene showed the bus toppled over onto its side next to the carriageway.

       "Apparently, the bus hit an incipient crash barrier in the area of the Krausnicker Berge Ost car park and overturned," police said.

       Nine people were seriously injured and several had to be flown to nearby hospitals by helicopter, according to a statement.

       The injured included people from Serbia, Sweden, Germany, and Israel, the DPA news agency reported.

       Police added that the bus was carrying 17 passengers of a private tour group and that an investigation into the accident had been launched.