The blast that tore through a Kabul mosque during evening prayers on Wednesday killed 21 people, Kabul police said on Thursday.
Police spokesperson Khalid Zadran said that another 33 people had been injured in the blast.
Witnesses had told newsmen the powerful explosion was heard in a northern Kabul neighbourhood, shattering windows in nearby buildings.
There was no immediate claim of responsibility for the blast and authorities did not publicly assign blame.
Since the Taliban seized power and toppled a U.S.-backed government a year ago, there has been a general decrease in bloodshed in the war-torn nation, according to the Taliban, who claim to be restoring stability.
However, there have recently been a number of sizable attacks in metropolitan areas, some of which were claimed by the Islamic State.
In a statement, Emergency Hospital, a clinic managed by an Italian NGO that specialises in treating war casualties, claimed it had admitted 27 victims of the explosions, including five children. According to Stefano Sozza, country director for Emergency in Afghanistan, two persons came dead and one patient passed away in the ER.
In August the hospital had treated 80 patients from six different mass casualty events, which includes major incidents such as blasts and mass shootings.
“The country is suffering the consequences of a very long conflict that has undermined its future,” Sozza said.