International humanitarian law and international human rights law are two distinct but complementary bodies of law.
The interplay between these two branches in the context of detention in armed conflict situations has been examined by the European Court of Human Rights in three cases stemming from the involvement of UK troops in Iraq: Al-Skeini v. United Kingdom (2011), Al-Jedda v. United Kingdom (2011) and Hassan v. United Kingdom (2014). The case of Serdar Mohammed v. Ministry of Defence deals with similar issues in the Afghan context.
Cases dealing with the treatment of detainees in armed conflicts have also been examined by the Inter-American Commission on Human Rights in Coard v. United States and Bámaca-Velasquez v. Guatemala.
Further information can be found on the issue of the interplay between IHL and IHRL in the context of detention on the ICRC website page on IHL and IHRL. Additionally, an article on the Al-Jedda case has been published in the International Review of the Cross (“The European Court of Human Rights’ Al-Jedda judgment: the oversight of international humanitarian law").