Preparations to set up the Croatian National Guard ( Zbor narodne garde – ZNG ) began on 12 April 1991 . Establishment of the ZNG as a police force with military capabilities was thought necessary by the Croatian authorities following armed clashes in Pakrac and at Plitvice Lakes in March and due to the possibility of further confrontation with the JNA . The ZNG , formally established on 23 April , was tasked with protection of the constitutional order , maintenance of public order , anti @-@ terrorist operations , protection of Croatia 's borders , territory , coast and territorial waters , as well as the protection of high @-@ value structures and high @-@ profile persons .