Transcript for US drops 'mother of all bombs' on ISIS forces in Afghanistan

The mother of all bombs CG VU 43 seat large powerful and accurately deliver weapon ABC news has learned at 7 PM local time. The US military dropped a GPU 43 seen here in a 2003 test. Marking the first time the 22000. Pound bomb has ever been used in combat. The intended target a series of nicest cave complexes in eastern Afghanistan along the border with Pakistan with this large ammunition your looking at. Haven't sharing that the cave in is destroyed it. With the first time gun that this is the latest in the ongoing fight against crisis the United States takes the fight against ice is very seriously. And in order to feed the group we must deny them operational space. Which we get the GBU 43 is the largest nonnuclear bomb in the US military's arsenal. So large it has to carry in the cargo hold. Of a C 130 military plane and then rolled out the back door this bombing comes less than a week after an American special forces soldier was killed during operations against the Islamic state in Afghanistan. The United States took all precautions necessary to prevent civilian. Casualties. And collateral damage as a result of the operation this was another very very successful mission. The Pentagon says that strike was designed to minimize risks to Afghan and US forces doing operations in the area. And to maximize destruction Tice as fighters and facilities today Norman ABC news Washington.

This transcript has been automatically generated and may not be 100% accurate.