Hundreds of thousands of Poles could be sacked because they were reported to have collaborated with the communist-era secret police, after the country’s right-wing government pushed through a law that critics say will spark a witch-hunt. The move is seen as central to the ”moral revolution” promised by the Law and Justice Party when it swept to power last year.

Polish farmworkers who travelled to southern Italy were kept in a ”concentration camp” where they were fed on little more than bread and water, expected to labour in the fields for up to 15 hours a day and beaten by guards who called themselves kapos, it was revealed recently.