WATCH: Spicer addresses U.S. bomb drop in Afghanistan in news briefing

White House Press Secretary Sean Spicer addressed questions about reports of a U.S. bomb drop in Afghanistan in Thursday’s news briefing.

The Pentagon says U.S. forces in Afghanistan dropped the military’s largest non-nuclear bomb on an Islamic State target in Afghanistan.

Adam Stump is a Pentagon spokesman. Stump says it was the first-ever combat use of the bomb, known as the GBU-43, which he said contains 11 tons of explosives. The Air Force calls it the Massive Ordnance Air Blast bomb. Based on the acronym, it has been nicknamed the “Mother Of All Bombs.”

Stump says the bomb was dropped on a cave complex believed to be used by IS fighters in the Achin district of Nangarhar province, very close to the border with Pakistan.

READ MORE: U.S. drops largest non-nuclear bomb on ISIS target in Afghanistan