Соответствующая норма
Practice Relating to Rule 128. Release and Return of Persons Deprived of Their Liberty
Section A. Release and return without delay
Croatia’s LOAC Compendium (1991) states that “unjustified delay in repatriation of POWs [prisoners of war]” falls under “grave breaches (war crimes)”. 
Croatia, Compendium “Law of Armed Conflicts”, Republic of Croatia, Ministry of Defence, 1991, p. 56.
Croatia’s Criminal Code (1997) provides:
Whoever in violation of the rules of international law, after the termination of a war or armed conflict, orders or imposes an unjustifiable delay in the repatriation of prisoners of war or civilians shall be punished. 
Croatia, Criminal Code, 1997, Article 166.