A huge explosion struck a mosque in the Afghan capital Kabul during evening prayers, with many people feared dead or injured, according to police.
A Taliban intelligence official told Reuters that as many as 35 people may have been wounded or killed, and the toll could rise further.
Al Jazeera quoted an official as giving a death toll of 20.
Videos show heavy smoke amidst buildings.
Kabul’s Emergency Hospital said it had received 27 wounded patients, including a seven-year-old child.
Witnesses told Reuters the powerful explosion was heard in a northern Kabul neighbourhood, shattering windows in nearby buildings.
Ambulances rushed to the spot.
“A blast happened inside a mosque… the blast has casualties, but the numbers are not clear yet,” Kabul police spokesman Khalid Zadran told Reuters.
The Taliban intelligence official, speaking on condition of anonymity, said the explosion was in a mosque, among worshippers in the Khair Khana area of Kabul.
The Imam of the mosque was among those killed, and the toll could still rise, the source added.
Intelligence teams were at the blast site and investigations were under way.
Other officials in the Taliban government did not reply to multiple requests to confirm the number of casualties.