In its second major display of military might in one week, the US dropped its most powerful non-nuclear bomb on ISIS positions in a remote part of Afghanistan.

Afghan officials said 36 militants were killed in the strike in Nangarhar province, near the Pakistan border. The US military previously estimated ISIS had 600 to 800 fighters operating in the area.

On Thursday night, a GBU-43/B Massive Ordinance Air Blast bomb (MOAB), capable of destroying an area equivalent to nine city blocks, was dropped on a network of fortified underground tunnels ISIS had been using to stage attacks on government forces.

The blast, from the weapon dubbed the “mother of all bombs,” destroyed three underground tunnels as well as weapons and ammunition, but no civilians were hurt, said an Afghan Defense Ministry spokesman.

A local resident living around two kilometers (1.5 miles) from the blast told CNN he heard an “extremely loud boom that smashed the windows of our house.”

“We were all scared and my children and my wife were crying. We thought it had happened right in front of our house,” he said.