A powerful explosion killed more than 50 worshippers after Friday prayers at a Kabul mosque, its leader said, amid a series of attacks on civilian targets in Afghanistan during Ramazan.

The blast hit the Khalifa Sahib mosque in the west of the capital in the early afternoon, said Besmullah Habib, deputy spokesman for the interior ministry, who said the official confirmed death toll was 10.

The attack came as worshippers at the Sunni mosque gathered after Friday prayers for a congregation known as Zikr — an act of religious remembrance practised by some Muslims but seen as heretical by some hardline Sunni groups.

Sayed Fazil Agha, the head of the mosque, said someone they believed was a suicide bomber joined them in the ceremony and detonated explosives. “Black smoke rose and spread everywhere, dead bodies were everywhere,” he told Reuters, adding that his nephews were among the dead. “I myself survived, but lost my beloved ones,” he said.

Resident Mohammad Sabir said he had seen people being loaded into ambulances.

“The blast was very loud, I thought my eardrums were cracked,” he said.

A hospital in downtown Kabul said it was treating 21 patients wounded in the blast and two patients were dead on arrival.