The man, identified as Cevat Soysal, has been flown to Turkey following his arrest in the former Soviet republic of Moldova.

Turkish Prime Minister Bulent Ecevit said he was the PKK's ''second man'' and had been arrested following "a very successful operation''.

Mr Soysal returns to Turkey

His capture comes five months after the PKK's leader Abdullah Ocalan, now facing the death sentence, was seized in Kenya.

But the rebel Kurdistan Workers Party (PKK) played down Mr Soysal's importance and insisted he was not seized by the Turkish authorities, but handed over by Moldova.

The BBC's Tom Kankkonen: "The Turkish forces are trying to stamp out the PKK"

It also denied he ranked as a senior figure.

''Our comrade Cevat Soysal was handed over to the Turkish state after being arrested by Moldova, not as a result of any secret operation by Turkey," a PKK statement said.

'Mass violence'

A photograph released by the Turkish intelligence service MIT showed a hooded man being helped down the steps of a small private aircraft.

Intelligence officials said Mr Soysal was involved in training PKK militants and organising pro-PKK activities in Europe and Middle East.

The MIT said Mr Soysal had been organising PKK teams in Turkey ''in developing mass violence''.

It said his importance had increased since Ocalan's arrest.

In an interrogation earlier this year, Ocalan said Mr Soysal was in charge of training rebels abroad, especially in Romania.

Political asylum

The leader of the tiny Kurdish community in Moldova, Hamghin Abdullah, said Mr Soysal was detained on 13 July when he left a house to make a telephone call to Germany, where he lives.

The PKK says Mr Soysal was not a senior leader

The reports come as the German Foreign Minister, Joschka Fischer, begins a visit to Ankara.

Germany, where Mr Soysal had been granted political asylum, denied playing any role in the arrest.

The arrest of Abdullah Ocalan earlier this year prompted a wave of protests by Kurdish sympathisers across Europe and bomb attacks in Turkey.

Ocalan, who led a 14-year armed campaign for a separate Kurdish homeland, was sentenced to death by a Turkish court last month.