Original sentence: In July 2009 the Bosnian Institute for Missing Persons began investigating the site of a mass grave
Edited sentence: According to Amor Masovic of the Institute for Missing Persons these are the dead from one of the buses.In July 2009 the Bosnian Institute for Missing Persons (IMP) began investigating the site of a mass grave.To date (6 August 2009) the remains of at least 51 deceased have been exhumed from a deep ravine.Two other buses were taken to a site that the IMP had worked at in 2003