Torben Andersen, spokesman for the Danish Spies travel agency, said a group of 27 Scandinavians - 11 Swedes, 10 Norwegians and six Danes - were on their way back from an excursion to nearby mountains on Friday when the bus tilted on a corner.
Mr Andersen said the other tourists sustained minor injuries and some were on their way back home.
He said the cause of the crash was unknown and that Turkish police were investigating.
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