North Korea Has a Secret Weapon: Underground Air Bases
Once located, there are three ways of dealing with the sites. The first and safest way to deal with them is to bomb them from above. This presents the least risk to allied forces, but it will also prove difficult to determine whether air or artillery strikes have had good effect. The use of bombs or artillery shells may cause cave-ins that prevent allied forces from entering an underground complex and exploiting any intelligence found inside.