Islamic State has claimed responsibility for an explosion at a mosque in Afghanistan's eastern Khost province that killed and wounded scores of people, its Amaq news agency reported on Saturday.
"Around 50 of the Afghan army were killed and 110 were wounded when a martyr blew himself up on Friday," the agency said.
Security officials in the area said on Friday that the blast at a mosque in an army base had killed at least 26 people and wounded 50.
The Taliban, who are waging a war to oust the Western-backed Afghan government and expel foreign forces from Afghanistan, have launched a series of high-profile attacks Taliban against Afghan security forces in recent weeks.
Hundreds of Afghan security guards have been killed, their checkpoints destroyed and weapons seized by the hardline Islamist fighters.
Friday's attack came three days after a suicide bomber detonated his explosives at a gathering of religious scholars in Kabul, the capital.
Officials said 55 scholars marking the birthday of the Prophet Mohammad were killed and more than 90 injured in the blast in a banquet hall.
"Around 50 of the Afghan army were killed and 110 were wounded when a martyr blew himself up on Friday," Amaq news agency said.