KABUL, Afghanistan (AP) — The suicide bomber stood in the middle of the dancing, clapping crowd as hundreds of Afghan children and adults celebrated a wedding in a joyous release from Kabul’s strain of war. Then, in a flash, he detonated his explosives-filled vest, killing dozens — and Afghanistan grieved again.

The local Islamic State affiliate claimed responsibility for the deadliest attack in the capital this year, with 63 killed and 182 wounded, while outraged Afghans questioned just how safe they will be under an approaching deal between the United States and the Taliban to end America’s longest war.

Stunned families buried the dead, some digging with their bare hands. One wounded survivor, Mohammad Aslim, still wore his bloodied clothes the day after the blast late Saturday. He and his friends had already buried 16 bodies, among them several close relatives, including a 7-year-old boy.

Aslim looked exhausted, and said he was waiting to bury more. Nearby, a man named Amanullah, who lost his 14-year-old son, said in anguish that the explosion had mangled the boy’s face so badly he could no longer recognize it.

“I wish I could find the pieces of my son’s body and put them as one piece into the grave,” he cried.

The emergence of the Islamic State affiliate in recent years might be the greatest threat to Afghan civilians as the U.S. and Taliban seek an agreement to end nearly 18 years of fighting. While the U.S. wants Taliban assurances that Afghanistan will no longer be used as a launch pad for global terror attacks, there appear to be no guarantees of protection for Afghan civilians.

The Taliban, which the U.S. hopes will help curb the IS affiliate’s rise, condemned Saturday’s attack as “forbidden and unjustifiable.”

The blast took place in a western Kabul neighborhood that is home to many in the country’s minority Shiite Hazara community. IS, which declared war on Afghanistan’s Shiites nearly two years ago and has claimed responsibility for many attacks targeting them in the past, said in a statement that a Pakistani IS fighter seeking martyrdom targeted a large Shiite gathering.