An explosion at a mosque in the eastern Afghan province of Khost has killed at least 10 people and the number may rise, a police official says.
Basir Bina, spokesman for the provincial police, said people were gathered after afternoon prayers in the mosque, which was also being used as a voter registration centre for parliamentary elections due in October.
No one immediately claimed responsibility for Sunday's attack, but both the Taliban and a local Islamic State affiliate reject democratic elections and have targeted them in the past.
IS is not known to have a presence in Khost, but has expanded its footprint into other areas in recent years.
Last month, an Islamic State suicide bomber attacked a voter registration centre in Kabul, killing 60 people and wounding at least 130 others.