WARSAW: Polish scientist Maciej Walczak has been released from prison in Iran and has returned to Poland, the Polish foreign ministry said on Saturday. “Achieving this goal was one of the priorities of Poland’s diplomatic and consular services last year,” the ministry said in a statement. In July, Iranian state television reported that the Revolutionary Guards had arrested several foreigners for acts that included taking soil samples in restricted areas. The report identified one of those as Walczak.