After this he spent a prolonged three years' military service with the National People's Army.

After having given up his studies for building industry technology at the Verkehrshochschule in Dresden, he underwent training as an air traffic controller.

In 1988 he passed an application test for a position as a broadcast news analyst for the DFF.

After doing voice roles for radio dramas, features, documentaries, and commercials between 1988 and 1991, the former chief presenter Werner Veigel took him to the Tagesschau in 1991 – initially Riewa was heard there as a voice actor, followed by a position as a broadcast news analyst from 1994 onwards.

His confessions about sexual intercourse with her annoyed his employer ARD, which he then apologised for, so it did not lead to any consequences.