Соответствующая норма
Nigeria
Practice Relating to Rule 128. Release and Return of Persons Deprived of Their Liberty
Nigeria’s Manual on the Laws of War provides: “Prisoners of war must be released and repatriated upon the cessation of the hostilities.” 
Nigeria, The Laws of War, by Lt. Col. L. Ode PSC, Nigerian Army, Lagos, undated, § 44.
According to the Report on the Practice of Nigeria, at the end of the Nigerian civil war in 1970, the inhabitants of the former Biafran enclave were released so that they could return to their respective towns. 
Report on the Practice of Nigeria, 1997, Chapter 5.4, referring to New Nigerian, 200 Ibos released, Lagos, 24 January 1970, p. 1.
According to the Report on the Practice of Nigeria, at the end of the Nigerian civil war in 1970, the inhabitants of the former Biafran enclave were released so that they could return to their respective towns. 
Report on the Practice of Nigeria, 1997, Chapter 5.4.