ISIS claimed it carried out this week's attack on a mosque on the outskirts of the Afghan capital that left 12 worshippers dead, SITE Intelligence Group reported.
The explosion happened inside a mosque in Shakar Darah district of Kabul province during Friday prayers and shattered the relative calm of a three-day ceasefire agreed between the Taliban and the Afghan government.
ISIS said its militants had placed an explosive device inside the mosque and detonated it after worshippers arrived to offer prayers on the second day of the Eid al-Fitr holidays, the US monitor of extremist groups said late Saturday.
The bombing killed the imam of the mosque, who was leading the prayers.
Friday was also the second day of a three-day ceasefire agreed by the Taliban and the government to mark Eid al-Fitr.
The ceasefire ended late on Saturday and so far no fighting between the two warring sides has been reported.
The temporary truce was announced after soaring violence since May 1, when the US military began formally withdrawing its last remaining troops from the country.