The 1991 killings of Serbs in Vukovar were a series of incidents in which Serbs living in and around Vukovar during the spring and summer of 1991 were subject to kidnappings and summary executions by armed thugs associated with the Croatian National Guard. These events began as the Croatian War of Independence was starting, prior to the start of the Battle of Vukovar in August of the same year. After the war, some criminal investigations were undertaken, including one of the notable perpetrators Tomislav Merčep, though on the whole the matter remains largely unresolved.