The United States dropped its biggest non-nuclear bomb, known as the "mother of all bombs," on ISIS positions in Afghanistan. The U.S. military has described it as a tactical move. The GBU-43/B Massive Ordinance Air Blast bomb was dropped Thursday night on a network of fortified underground tunnels that ISIS had been using to stage attacks on government forces. The strike killed 36 ISIS fighters, Afghan officials said. The bomb is GPS-guided and has the power to destroy an area equivalent to nine city blocks. The blast destroyed three underground tunnels as well as weapons and ammunition but no civilians were hurt, according to Afghan and U.S. officials.