A rocket has hit a mosque in Afghanistan's eastern Nangarhar Province, killing at least five worshippers and wounding four others.
The attack in Nangarhar's Achin district occurred during evening prayers on October 30, district Governor Haji Ghalib said.
Ghalib and other local officials blamed the attack on the Islamic State (IS) extremist group.
A spokesman for Nangarhar's police chief said security forces had arrested two suspects, one of whom was a foreign national.
Afghan officials say the IS extremist group has been building up its presence in Afghanistan.
Afghan media described Achin as a "major hub" for IS militants in recent months.