Career
In the, Siebert has two gold medals with the East German relay team in 1978 and 1979, and a bronze medal from 1977. He also has three individual medals gold medal from the 20 km in 1978 and two bronzes from the 10 km in 1975 and 1978. After retiring from competition he became a coach.
He has coached in Germany, China and Belarus.
He returned to his coaching role with the Belarusian national biathlon team in January 2012 after spending much of the previous year ill with cancer. However, Siebert stepped down from this role ahead of the 2014-2015 season due to health issues.
All results are sourced from the International Biathlon Union. Olympic Games 1 medal (1 silver) World Championships 6 medals (3 gold, 3 bronze) *During Olympic seasons competitions are only held for those events not included in the Olympic program
Individual victories 8 victories (6 In, 2 Sp).