February 2023: Senior PSNI officer Detective Chief Inspector John Caldwell is shot at a sports complex in Omagh where he had been coaching football. April 2015: A bomb explodes outside the Probation Service office in Derry. October 2011: A bomb explodes outside UK City of Culture offices in Derry. Constable Ronan KerrApril 2011: Catholic PSNI officer Ronan Kerr (25) is murdered by a car bomb at his home in Omagh. PSNI officer Stephen CarrollMay 2008: A Catholic PSNI officer sustains serious leg injuries when a bomb detonates under his car near Castlederg, Co Tyrone.