KABUL, Afghanistan – An Afghan hospital official says an explosion inside a minority Shiite mosque in western Herat, on the border with Iran, has killed at least 20 people.

The official, Dr. Mohammed Rafique Shehrzad, said 20 bodies were brought to his Main Hospital in Herat city, the capital of western Herat province Monday night, soon after the blast shattered the late evening.

Shiites are a minority in Afghanistan and have been threatened by the Islamic State affiliate that operates in the country’s east.

No one immediately took responsibility for the attack on the Jawadia Mosque in Herat.