on-don, Russia, May 01, 2010, SPA --Rescue workers say a homemade bomb exploded at a racetrack in southern Russia and 13 people were taken to the hospital with injuries. No one was reported killed. Emergency Situations Ministry duty officer Marat Prokopenkov says the bomb exploded near a VIP box during a horse race in the city of Nalchik, according to a report of the Associated Press. Nalchik is the capital of Kabardino-Balkaria, one of the predominantly Muslim provinces of Russia's North Caucasus. No one immediately claimed responsible for Saturday's bombing, which occurred as Russia celebrated May Day.