The United States has dropped a 10,000-kilogram bomb, with an explosive yield of 11 tonnes, over a remote area in the east of Afghanistan bordering Pakistan.
It marks the first use ever of the United States' biggest non-nuclear bomb.
The bomb has been nicknamed the "mother of all bombs," a twist on the acronym MOAB, standing for Massive Ordnance Air Blast.
White House press secretary Sean Spicer says the weapon was chosen to best target and destroy a tunnel complex of the self-proclaimed Islamic State, or ISIS.
Sean Spicer says US forces took what he calls "all precautions necessary to prevent civilian casualties and collateral damage."
President Trump has rejected claims the choice of weapon was intended to send a message to North Korea.
Meanwhile, some experts have dismissed analysis that the non-nuclear bomb represents an escalation in Afghanistan.
The director of the US air force's School of Deterrence, Dr Adam Lowther, says the weapon has nothing near the force of the nuclear bombs dropped on Japan in World War Two.
He says those bombs had an explosive yield 75 times greater.
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