The Kurdistan Freedom Falcons (TAK) said they bombed the bus because Turkey "is planning a massacre of the Kurdish people" and has adopted "a concept of aggression" against jailed Kurdish rebel leader Abdullah Ocalan, it said.

The Turkish authorities say TAK is a front used by the Kurdistan Workers' Party (PKK), which has waged a bloody 26-year insurgency in the southeast, especially when attacks claim civilian casualties.

The PKK has said TAK is a splinter group outside its control.