The new charges, listed in a 139-page indictment alleging murder, extortion and separatist activity - are to be considered on Friday by the one military and two civilian judges who are expected to hear the full case next month.

"Under the direction of the accused Abdullah Ocalan...PKK gangs displayed complete savagery in their attacks on civilians; they killed women, men, young, old, at random and did not stop at children," the documented is reported to say.

The rebel leader will be charged with treason, a crime carrying the death penalty.

'Terrorist acts'

Prosecutors have already demanded that Mr Ocalan be executed for separatist killings and terrorist acts alleged to have been carried out by his group, the PKK.

His capture sparked Kurdish protests around the world

Chief Prosecutor Cevdet Volkan said the indictment requests Mr Ocalan's death sentence under Article 125 of the Turkish Penal Code, which governs crimes of "treason and crimes committed against country and sovereignty of the state."

Prosecutors say the rebel leader has already confessed to his crimes. "It is true that I carried out the leadership of this organisation and I pioneered an armed struggle on Turkey's soil," the prosecution document quotes him as saying.

Prison island

Mr Ocalan has been held on the heavily guarded island of Imrali, south of Istanbul, since he was arrested in February under an international warrant.

The BBC's Ankara Correspondent, Chris Morris, says the new indictment is expected to be combined with existing cases, begun in Mr Ocalan's absence.

He will not be present in court himself on Friday because of security concerns.

A special courthouse is being constructed on the island prison for next month's trial, but it is unclear whether any outside observers or journalists will be allowed to attend the trial.

Parliamentary decision

If Mr Ocalan is found guilty, the judges have no alternative but to order his execution by hanging.

But a decision to proceed with an execution must be ratified by parliament, which has not accepted any capital punishment case since 1984.