As many as 36 suspected Islamic State militants have been killed in Afghanistan after the US dropped a GBU-43 bomb, also known as 'the mother of all bombs', the Afghan Defence Ministry says.
The claims have not been independently verified, but ministry spokesman Dawlat Waziri said no civilians were harmed in the massive blast that targeted a network of caves and tunnels.
"No civilian has been hurt and only the base which Daesh used to launch attacks in other parts of the province was destroyed," Mr Waziri said in a statement, using the Arabic term for Islamic State, which has established a small stronghold in eastern Afghanistan.
It's the first the US has dropped a GBU-43 bomb - the largest non-nuclear device it has ever used in combat.
The bomb was dropped from an MC-130 aircraft in the Achin district of Nangarhar province, close to the border with Pakistan, a Pentagon spokesman said.
The GBU-43 is a 21,600 pound (9,797 kg) GPS-guided munition and was first tested in March 2003, just days before the start of the Iraq war.
General John Nicholson, the head of US and international forces in Afghanistan, said the bomb was used against caves and bunkers housing fighters of the Islamic State in Afghanistan, also known as ISIS-K.
"This is the right munition to reduce these obstacles and maintain the momentum of our offensive against ISIS-K," General Nicholson said in a statement.