The moment the American military dropped "the mother of all bombs" on an Islamic State target in Afghanistan, killing 36 militants, was caught on video.

The footage, released by Washington on Friday, shows crosshairs hovering over a spot at the foot of a mountain range in the east of the country.

Within seconds, the largest non-nuclear bomb America has ever used in combat hurtles towards an Isil complex of caves and tunnels.

Smashing into the earth, it throws up a thick cloud of smoke as rubble flies through the air.