Macomb, Ill.- Authorities have arrested one person in connection with a fatal stabbing in Macomb. According to the Macomb Police Department, authorities are investigating an altercation that escalated into a stabbing that killed one person Sunday, July 24th, in the Macomb Downtown Square. Macomb Police have arrested one person of interest in the case and assure there is no threat to the public. The WIU Office of Public Safety, the McDonough County Sheriff's Office, Illinois State Police, and Crime Scene Units are assisting with the investigation.