Blasts close to a secondary school in the Afghan capital Kabul have left at least 50 people dead and more than 100 injured, officials say.
The explosions took place as students were leaving the building on Saturday, with pictures on social media showing abandoned school bags in the street.
Most of the victims were girls, a ministry of education spokeswoman said.
No-one has admitted carrying out the attack in Dasht-e-Barchi - an area often hit by Sunni Islamist militants.
Afghan government officials blamed Taliban militants for the attack, but the group denied any involvement.
The explosions are believed to have been caused by a car bomb and two improvised explosive devices planted in the area.
The neighbourhood in western Kabul is home to many from the Hazara minority community, who are of Mongolian and Central Asian descent and are mainly Shia Muslims.
Almost exactly a year ago, a maternity unit at the local hospital was attacked, leaving 24 women, children and babies dead.
The exact target for Saturday's bloodshed is unclear.
The blasts come against a backdrop of rising violence as the US looks to withdraw all its troops from Afghanistan by 11 September.
Reports from Kabul say the city was busy with shoppers ahead of this year's celebrations for Eid al-Fitr next week.
Students were also streaming from the school. Najiba Arian, ministry of education spokeswoman, told Reuters news agency the government-run school was open to boys and girls.
Most of the those hurt were girls, who study in the second of three sessions, according to Ms Arian.
Several witnesses described hearing three separate explosions, while one woman told AFP news agency she had seen "many bloodied bodies in dust and smoke".
"I saw a woman checking the bodies and calling for her daughter," the woman, Reza, said. "She then found her daughter's bloodstained purse after which she fainted and fell to the ground."
The US state department condemned "the barbarous attack".
"We call for an immediate end to violence and the senseless targeting of innocent civilians," it said.
The European Union's mission in Afghanistan said on Twitter that "targeting primarily students in a girls' school, makes this an attack on the future of Afghanistan".
Analysis by Secunder Kermani, BBC Afghanistan correspondent
So many places in Afghanistan have endured so much pain, but the Dasht-e-Barchi neighbourhood in Kabul has suffered horrendously.
The neighbourhood is populated by members of Afghanistan's Hazara ethnic minority. As followers of Shia Islam, the Islamic State group (IS) views them as heretics, and has carried out a vicious campaign, attacking the softest of targets.
Dozens have been killed in bombings at sports halls, cultural centres, and places of education in particular.
Last year, and in 2018, IS suicide bombers struck tuition centres in the area killing more than 70 people. IS is not part of the peace talks between the Taliban and Afghan government, which in any case are currently stalled.
As of yet, there's been no claim for the attack on Saturday. However, IS continues to carry out assassinations and bombings in Kabul and the city of Jalalabad, despite having recently lost much of the territory it once controlled in the east of the country.
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