Related Rule
Sri Lanka
Practice Relating to Rule 158. Prosecution of War Crimes
Sri Lanka’s Geneva Conventions Act (2006) states:
2. (1) Any person, whether a citizen of Sri Lanka or not, who within or outside Sri Lanka –
(a) commits or attempts to commit; or
(b) aids, abets, conspires or procures the commission by any other person of, a grave breach in terms of the relevant Articles of the Conventions as are set out in Schedule I, Schedule II, Schedule III and Schedule IV to this Act and are also enumerated in subsection (2) of this section, shall be guilty of an offence.
3. Subject to the provisions of section 6, every prosecution for an offence in terms of section 2 shall be by way of direct indictment filed by the Attorney-General. 
Sri Lanka, Geneva Conventions Act, 2006, Sections 2–3.
The Act includes the following paragraph from the 1949 Geneva Conventions:
Each High Contracting Party shall be under the obligation to search for persons alleged to have committed, or to have ordered the commission of such grave breaches, and shall bring such persons, regardless of their nationality, before its own courts. It may also, if it prefers, and in accordance with the provisions of its own legislation, hand such persons over for trial to another High Contracting Party concerned, provided such High Contracting Party has made out a prima facie case. 
Sri Lanka, Geneva Conventions Act, 2006, Schedule I: Article 49, Schedule III: Article 129, and Schedule IV: Article 146; see also Schedule II: Article 50.