BERLIN, June 21 (Reuters) - German prosecutors on Monday said they arrested a university research assistant accused of working for the Russian secret service. The man, identified as Ilnur N., according to German reporting rules, worked as a research assistant for a scientific and technical professorship at a German university, the prosecutors said. He met a member of the Russian foreign secret service at least three times between October 2020 and June 2021 and passed on information in return for cash payments, it added. The man was arrested on Friday, June 18.