The attack, reportedly by four people, took place during Friday prayers in the southern Kandahar province. It is the second in a week targeting a Shiite mosque.
In recent weeks, protesters have been killed and arrested, an opposition party dissolved and an independent newspaper closed. Some accuse President Trump of prioritizing arms sales over human rights.
The Islamic State has claimed responsibility for one attack, and several other bombings followed across the city. The attacks continue an especially bloody week in the Iraqi capital.
Demonstrators took to the streets in the Afghan capital on Wednesday to protest the killings of seven members of an ethnic minority group by Islamist militants.
