KABUL -- A suicide bombing at a large gathering of Afghan clerics in Kabul has killed at least 43 people and wounded 83 others, officials say.
Health Ministry spokesman Wahid Majrooh told RFE/RL that 24 of the injured were in critical condition following the November 20 blast, which targeted a gathering of scholars from across Afghanistan at a wedding hall to mark the Prophet Muhammad's birthday.
A number of participants were said to be unaccounted for.
The explosion was caused by a suicide bomber, according to Interior Ministry spokesman Najib Danish.
A manager of the hotel where the blast occurred told the AFP news agency that a suicide bomber blew himself up in the middle of the gathering.
Hundreds of family members and relatives gathered outside local hospitals, looking at lists of those killed and wounded.
There was no immediate claim of responsibility for the bombing, one of the deadliest attacks to strike the Afghan capital in months.
Calling the latest attack "un-Islamic" and an "unforgivable crime," Afghan President Ashraf Ghani called declared a national day of mourning on November 21.
The U.S. ambassador to Kabul, John Bass, tweeted that he was "sickened and saddened by tonight's terror attack."
The United Nations Assistance Mission in Afghanistan said it was "outraged by Kabul bombing when communities across Afghanistan are marking day of special religious significance."
The Taliban and the Islamic State (IS) militant groups have targeted Muslim religious scholars aligned with the Afghan government in the past.
Afghan security forces have struggled to counter attacks from the two groups since the withdrawal of most NATO combat troops in 2014. The remaining Western forces mainly train and advise the Afghan military, although some are still occasionally caught in firefights.
A local affiliate of the IS group claimed a suicide bombing in June that targeted a meeting of the country's top religious body in the capital. That attack killed at least seven people, including several clerics.
The Afghan Ulema Council had issued a religious order, or fatwa, declaring suicide attacks forbidden, or "haram," under the principles of Islam.