Related Rule
Ukraine
Practice Relating to Rule 108. Mercenaries
Section B. Status of mercenaries
Ukraine’s IHL Manual (2004) states:
1.2.25. … [M]ercenaries are unlawful participants of the hostilities.
1.2.25.2. … [M]ercenaries shall not have the right to be prisoners of war and are subject to punishment for their actions. However, their punishment may only be imposed by a competent tribunal. 
Ukraine, Manual on the Application of IHL Rules, Ministry of Defence, 11 September 2004, §§ 1.2.25 and 1.2.25.2.
Ukraine’s Criminal Code (2001) provides:
Participation, without permission of government bodies in charge, in armed conflicts of other States with the purpose of gaining financial profit shall be punishable with deprivation of liberty for a term of five to ten years. 
Ukraine, Criminal Code, 2001, Article 447(2).