KABUL, Afghanistan — A suicide blast at a mosque in an army base in eastern Afghanistan on Friday killed at least 26 people and wounded 50, authorities said.

One security official said the victims had gathered for Friday prayers in the Ismail Khel district of Khost province.

All those killed in the suicide attack were working for the Afghan security forces, according to Capt. Abdullah, a military spokesman in Khost who goes by only one name.

There was no immediate claim of responsibility.

However, the Taliban has launched a series of high-profile attacks against Afghan security forces in recent weeks. The militants are waging a war to oust the Western-backed Afghan government and expel foreign forces from the country.

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 explosives at a gathering of religious scholars in Kabul, killing 55 people.

Officials said more than 90 others were injured at the event marking the birthday of the Prophet Muhammad in a banquet hall.