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- Harry 'Breaker' Harbord Morant (1864 – 27 February 1902) convicted and executed for illegal summary executions of Boer and other prisoners during the Second Boer War.
- Ali Hassan al-Majid, (1941–2010) Iraqi Baathist Defense Minister, executed for war crimes, crimes against humanity, genocide
- Abid Hamid Mahmud, (died 2010) Iraqi military officer
- Milan Martić (born 1954), President and defence minister of Croatian Serbs during Croatian War of Independence, sentenced to 35 years
- Vinko Martinović (born 1963), Bosnian Croat sentenced to 18 years
- Josef Mengele (1911-19??) SS Officer and Camp doctor at the Auschwitz Death camp, notorious for his medical experiments; called "the angel of death".
- Mile Mrkšić (born 1947), Serb General convicted to 20 years for the Vukovar massacre
- Zdravko Mucić, Bosnian Croat sentenced to 9 years for Čelebići prison camp
Read more about this topic: List Of Convicted War Criminals