"A auto bomb blast happened first, and then two more explosions occurred near the girls school in Kabul", said TOLOnews, quoting a schoolteacher, who added that the majority of victims are girls.
The Taliban and United States last year signed an agreement to end the 20-year war, which started with USA and allied forces invading Afghanistan following the 2001 September 11 attacks in the United States by al Qaeda, whose leader, Osama bin Laden, was being given shelter by the Taliban government.
The toll in the multiple blasts outside a girls' school in Afghanistan Capital Kabul crossed 50, while more than 100 were injured, TOLO News reported on Sunday, quoting the country's ministry of interior.
Residents were shopping ahead of this week's Eid al-Fitr holiday - which marks the end of the Islamic holy month of Ramadan - when the blasts occurred.
On Sunday relatives began burying the dead at a hilltop site known as "Martyrs Cemetery".
The Sunnis in Kabul also expressed their displeasure with the Shiites.
Bodies in wooden coffins were lowered into graves one by one by mourners still in a state of shock and fear, an AFP photographer said. "Their bodies piled on top of each other".
Witnesses said the carnage outraged area residents, who even attacked the ambulances, hampering rescue efforts because they were so upset with the government for failing to provide better security.
"But what they got (in return) was a massacre". "Let us pray for the victims of the terrorist attack in Kabul, an inhumane action that struck so many girls as they were coming out of school".
No group claimed that attack, but President Ashraf Ghani blamed the Taliban and the Islamic State group.
"With scores murdered, this unforgivable attack on children is as assault on Afghanistan's future, which can not stand".
No-one immediately claimed responsibility for the attack, and Taliban spokesman Zabihullah Mujahid told reporters in a message that only IS could be responsible for such a heinous crime.
But the group has clashed in near-daily battles with Afghan forces in the rugged countryside even as the USA military reduces its presence.
The Taliban has denied carrying out attacks in Kabul since February past year, when they signed a deal with the United States that paved the way for peace talks and withdrawal of the remaining USA troops.
The Taliban have condemned the attack and denied responsibility. "Children must never be the target of violence", it said, urging the country's warring sides to protect human rights.
Ambulances rushed to evacuate the wounded from the scene of the blast near Syed Al-Shahda school, in the Shia majority area of Dasht-e-Barchi, in the west of the city.
An injured man is transported to a hospital after a blast in Kabul, Afghanistan May 8, 2021.
On October 24, a suicide bomber blew himself up at a tuition centre in the same district, killing 18 people including students in an attack that also went unclaimed.