At least 62 people were killed by a blast inside an Afghan mosque during Friday prayers, according to officials, a day after the United Nations said violence in the country had reached "unacceptable" levels.
The attack – the year's second most deadly to date – took place in the eastern province of Nangarhar and also wounded at least 33 people, the provincial governor's spokesman Attaullah Khogyani told AFP.
The blast was carried out with "explosives that were placed inside the mosque", Khogyani said, though other sources - including the Taliban - said the building may have been hit by a mortar.
A spokesman for the Taliban said the group has "condemned this atrocity in the strongest terms" and labelled it a "major crime".
ISIS has also been active in Nangarhar.
Attaullah Khogyani, spokesman for the provincial governor, said the victims included children and that the number of casualties could still rise.
The blast came a day after the UN reported that an "unprecedented" number of civilians were killed or wounded in Afghanistan from July to September.
The figures – 1,174 deaths and 3,139 injured from July 1 until September 30 – represent a 42 per cent increase compared to the same time period last year.
The UN report, which also charted violence so far this year, underscored how "Afghans have been exposed to extreme levels of violence for many years" despite promises by all sides to "prevent and mitigate harm to civilians".
It also noted the absurdity of the ever-increasing price paid by civilians given the widespread belief that the war in Afghanistan cannot be won by either side.
"Civilian casualties are totally unacceptable," said the UN's special representative in Afghanistan, Tadamichi Yamamoto, adding they demonstrate the importance of talks leading to a ceasefire and a permanent political settlement.
The UN report laid most of the blame for the spike in deaths on "anti-government elements" such as the Taliban, who have been carrying out a bloody insurgency in Afghanistan for more than 18 years.
July alone saw more casualties than in any other month on record since the United Nations Assistance Mission in Afghanistan (UNAMA) began documenting the violence in 2009.
The first six months of 2019 had seen casualties drop slightly compared to previous years.
But the violence has surged so far in the third quarter that it yanked the overall total for the year back on par with the bloodiest since Nato withdrew its combat forces at the end of 2014.