In early October 1991, Montenegrin forces and the Yugoslav People's Army (JNA) began the Siege of Dubrovnik. The JNA's bombardment of Dubrovnik, including that of the Old Town — a UNESCO World Heritage Site — provoked international condemnation, and became a public relations disaster for Serbia and Montenegro, contributing to their diplomatic and economic isolation, as well as proving to be detrimental to Montenegro's internal stability and inter-ethnic relations within the republic.