Kurdish rebels say they have shot down a Turkish military helicopter, killing at least seventeen soldiers near the city of Hakkari, in the south east of the country.

The Turkish authorities confirmed a helicopter had crashed returning from an operation against PKK rebels but did not say why.

The incident came as Turkish diplomats flew to Italy to request the extradition of the PKK separatist leader, Abdullah Ocalan.

Italy has already said it will not extradite Mr Ocalan to Turkey because it has the death penalty.

But Turkey has warned of a trade embargo if he is not handed over.