Related Rule
Australia
Practice Relating to Rule 117. Accounting for Missing Persons
Australia’s Defence Force Manual (1994) provides: “As soon as possible each party to an armed conflict must search for those reported missing by the enemy.” It adds: “In order to facilitate the search for missing combatants … each protagonist shall record … information for each person detained, imprisoned or otherwise held in captivity for a period of two weeks, or who has died.” 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, §§ 994, 996 and 997.
Australia’s LOAC Manual (2006) states:
9.99 As soon as possible each party to an armed conflict must search for those reported missing by the enemy.
9.101 The search. As soon as circumstances permit, but at the latest once active hostilities have ceased, all protagonists to the conflict shall commence to search to the fullest extent possible for persons reported missing by one of the belligerents …
9.102 Particulars of missing persons. In order to facilitate the search for missing combatants … each of the protagonists shall … record … information for each person detained, imprisoned or otherwise held in captivity for a period of two weeks, or who has died. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, §§ 9.99 and 9.101–9.102.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).
Australia’s Defence Force Manual (1994) provides:
Any request and all information which may assist in tracing or identifying [missing] persons shall be transmitted through the Protecting Power or the Central Tracing Agency of the ICRC or the national Red Cross societies. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, § 994.
The manual further states: “The report of a missing person is to be notified by each belligerents’ National Bureau direct, or through a Protecting Power to the Central Agency of the ICRC.” 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, § 996.
Australia’s LOAC Manual (2006) states:
9.99 … Any requests and all information which may assist in tracing or identifying such persons shall be transmitted through the Protecting Power or the Central Tracing Agency of the ICRC or the national Red Cross societies.
9.101 … The report of a missing person is to be notified by each belligerent’s national bureau direct, or through a protecting power to the Central Tracing Agency of the ICRC. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, §§ 9.99 and 9.101.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).
According to the Report on the Practice of Australia, diplomatic correspondence and press releases show that, in 1984, a joint Australian-Vietnamese operation was launched “to search for the remains and resolve the cases” of six Australian personnel listed as “missing in action” in Viet Nam and “to follow up any other case which might subsequently be drawn to its attention”. The report states that the motive for the operation appears to be based primarily on political considerations (i.e. improvement of bilateral relations with Viet Nam). 
Report on the Practice of Australia, 1998, Chapter 5.2.
Australia’s Defence Force Manual (1994) provides:
The request for information relating to either the missing or the dead must be humanitarian in nature and stem from the need for relatives to be notified of their whereabouts and subsequent repatriation, or re-interment. Should there be any controversy resulting from the request for information, the humanitarian needs and interests of the families concerned must prevail. 
Australia, Manual on Law of Armed Conflict, Australian Defence Force Publication, Operations Series, ADFP 37 – Interim Edition, 1994, § 995.
Australia’s LOAC Manual (2006) states:
The request for information relating to either the missing or the dead must be humanitarian in nature and stem from the need for relatives to be notified of their whereabouts and subsequent repatriation, or re-internment. Should there be any controversy resulting from the request for information, the humanitarian needs and interests of the families concerned must prevail. 
Australia, The Manual of the Law of Armed Conflict, Australian Defence Doctrine Publication 06.4, Australian Defence Headquarters, 11 May 2006, § 9.100.
The LOAC Manual (2006) replaces both the Defence Force Manual (1994) and the Commanders’ Guide (1994).