Best-selling crime writer Lynda La Plante's 1993 novel Entwined contains passages lifted from Auschwitz survivor Olga Lengyel's 1947 memoir Five Chimneys, news reports said on Saturday.

The multimillionaire British author denied plagiarism but admitted to The Sydney Morning Herald that a research assistant may have been the culprit.

La Plante, who shot to fame with the television series Prime Suspect starring Helen Mirren, was taken to task by an eagle-eyed Australian reader who recognised several almost identical passages about the workings of the Auschwitz death chambers.

Where Lengyel had written that the ovens could dispose of "three hundred and sixty corpses every half hour, which was all the time it took to reduce human flesh to ashes," La Plante wrote "three hundred and sixty corpses every half hour - all the time it took to reduce human flesh to ashes".

Malcolm Knox, the newspaper's literary editor, commented that "outsourcing any task always has its perils, and when asked how much material her assistants put into her novels and how she checks that they are not plagiarising other books, La Plante's lawyers said Entwined was unique and her other books were not "researched on the same basis".