Turkish state prosecutors have charged one of the lawyers acting for the detained rebel Kurdish leader, Abdullah Ocalan, with aiding and abetting the illegal Kurdistan Workers' Party, the PKK.
The state Anatolia news agency said the accusations against Niyazi Ulgan followed the recent arrest of his secretary, Belgian-born Sibel Ceylan, at Istanbul airport.
The agency said she had been carrying documents given to her by Mr Ulgan, including a petition to the European Court of Human Rights.
Mr Ocalan goes on trial next Monday on charges of treason, which carry the death penalty.
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