The bomb also destroyed the terrorist's weapons storage facilities and completely destroyed their underground tunnel system, which they used to evade USA military drone strikes.
The GBU-43/B Massive Ordnance Air Blast bomb - dubbed the "Mother Of All Bombs" - was unleashed in combat for the first time, hitting IS positions in eastern Nangarhar province on Thursday.
"This is the right munition to reduce these obstacles and maintain the momentum of our offensive against Isis-K", he added, using the USA military's acronym for the Isis affiliate. These death tolls are much higher than the initial figure of 36 IS fighters provided by Afghan officials. Afghan News Agency on Twitter, become a fan on Facebook.
The GPS-guided bomb is capable of destroying an area equivalent to nine city blocks.
"This weapon was used against Isis-K and their sanctuary inside Afghanistan", NATO forces commander General John Nicholson said., according to the AP.
Unlike the MOAB, which uses conventional ordnance, the FOAB aka "Big Daddy" is Thermobaric - meant to burn its targets.
Nicholson gave a vague response to reporters' questions on who ordered or greenlighted the strike, saying only that he enjoyed a certain amount of "latitude" to make decisions in his chain of command.
"The enemy had created bunkers, tunnels and extensive mine fields, and this weapon was used to reduce those obstacles so that we could continue our offensive in Nangarhar", General John Nicholson, the top United States commander in Afghanistan, said.
Army General John W Nicholson, commander of U.S. forces in Afghanistan, said the strike was created to minimise the risk to Afghan and USA forces conducting clearing operations in the Achin area "while maximising the destruction" of Isis fighters and facilities.
But former President Hamid Karzai accused the United States of using Afghanistan as "a testing ground for new and unsafe weapons".
No civilians were killed in the explosion, Mr Shinwary said.
On Tuesday, the US-led coalition in Syria killed 18 of its own allies from the Syrian Democratic Forces in what was described as a misdirected airstrike.
But President Donald Trump said Thursday that the Afghanistan bombing was "another successful job". It came a week after he authorized a U.S. missile strike against a Syrian government air base - the first USA strike against the Syrian government in the country's six-year civil war.
Residents in Afghan villages near the target area felt Thursday's powerful strike.
"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. The weapon's blast generates a mushroom cloud that can be seen from about 20 kilometers away.
The massive bomb was dropped after fighting intensified over the past week and US-backed ground forces struggled to advance on the area.
Afghan security force personnel take part in an ongoing operation against an Islamic State (IS) militant stronghold in Achin district of Nangarhar, eastern Afghanistan on April 14, 2017.
Sher Nabi, a commander with the Afghan Local Police, told the LA Times earlier this week that the bomb had landed about a half mile outside the town of Shogal near the border with Pakistan, and that "many militants" were killed. The BLU-82 was used multiple times in the early stages of the war in Afghanistan when U.S. forces were closing on Osama bin Laden in the mountains of Tora Bora on the Afghan-Pakistan border. The rocky landscape is dotted with caves and defensive tunnels, making it easy to hold and hard to attack, according to Nic Robertson, CNN's global diplomatic editor, who has reported from the Afghan mountains.
USA personnel in the country are engaged mostly in training local forces and carrying out counter-terrorism operations, according to the AP.
Mr Crowley, a former U.S. air force colonel, said the bomb was "like creating a minor quake in that particular area".
It produces more energy than normal weapons but is harder to control. The Thursday deployment was the first time the bomb has ever been used in the field since its testing in 2013. The United States took "all precautions necessary to prevent civilian casualties and collateral damage", he said. The target set has been expanded to include targets buried under softer surfaces, such as caves or tunnels.
As originally conceived, the MOAB was to be used against large formations of troops and equipment or hardened above-ground bunkers.