At least 15 persons have been killed and 38 others injured in two suicide explosions in central Tikrit, the center of Salahal-Din Province on Thursday, a Salahal-Din medical source reported. \"The semi-final result of two suicide explosions on Thursday morning in central Tikrit early has reached 15 killed, including four police and Army men and more than 38 wounded,\" the medical source told (Aswat al-Iraq) news agency. Meanwhile, a security source told Aswat al-Iraq that \"Salahal-Din\'\'s Operations Command had imposed a curfew on Tikrit city, whilst the security bodies began an inspection campaign against existence of booby-trapped cars or possible attackers.