The authorities in Poland have issued a warrant for the extradition of a Polish-born British woman over her role in the Stalinist show trials of the nineteen-fifties.

The woman, Helena Brus, was the country's chief military prosecutor at the time.

She is accused of organizing the unlawful arrest and execution of a hero of the Polish wartime resistance, General Emil Fieldorf, who was hanged for killing Soviet soldiers after a one-day trial.

He was officially pardoned after the collapse of communism.

Mrs Brus is seventy-nine and married to an Oxford University professor; she denies the charges.