The INP commissioner is assisted by a staff of senior officers who form the National Headquarters. This staff consists of five major generals, each heading one of the force's five departments: policing and security, investigation and crime fighting, logistics, personnel and planning, and organization. The country is divided into four police districts, which are divided in subdistricts and stations. The patrol arm of the INP is responsible for public peace and security, law enforcement, crime prevention, and public order. The INP, together with the Israeli Defense Force, acts as Israel's Coast Guard. The Department of Investigation and Crime Fighting is staffed by 2,500 investigators. Three nationwide investigation units address fraud and white-collar crime, organized crime and serious crime, and internal affairs (investigation of police officers). Israel is a full member of Interpol and has close relations with other members of this agency.