Authorities in Philadelphia are investigating the death of the father of former National Security Adviser H.R. McMaster as suspicious, 6ABC reports. H.R. McMaster Sr., a Korean War veteran, died of blunt force trauma to the head on April 13 at a retirement community in Roxborough. The Philadelphia police homicide unit, the Philadelphia district attorney, the attorney general’s office, and the health department are all now reportedly investigating allegations he was left to die in a chair after falling and hitting his head. Staffer at the facility also reportedly told McMaster’s family that certain documents relating to his death were falsified. Philadelphia police searched the facility Tuesday, though no details on their findings have been released, 6ABC reported.