Assessing of construction and use of underground warfare with the legal principles of armed conflict

Non-governmental armed groups have always resorted to various innovations in order to balance their forces. Tunnels warfare are unique innovations that increase their military capability and double their ability to defeat enemies. The construction of tunnels in wars has always been attractive to users for their various applications, which has become a winning strategy. Since the global powers' intelligence and military capabilities have been enhanced, underground tunnels have emerged as an impenetrable haven for non-governmental armed groups, balancing unequal military forces on both sides. Inside underground structures, soldiers and military personnel can conduct military operations without identification and with minimal exposure to enemy surveillance and intelligence systems. But tunnels have not yet been the subject of any armed conflict law, and the legal status of it remains questionable. The main task of the research is to find a legal framework on underground warfare to reveal the unknown aspects of this warfare. The use of tunnels, despite its many legal challenges, seems to be a function of the general principles of international humanitarian law, which have distinct legal effects as a weapon or method of warfare.