While it has been months since The Taliban have claimed a major attack in Kabul, the group has been conducting blistering attacks on security forces across Afghanistan, including a massive, days-long onslaught on the eastern city of Ghazni during the past week.
"UNICEF is gravely concerned about the growing violence across Afghanistan, especially over the past week, where children continue to be the hardest hit", UNICEF Executive Director Henrietta Fore said in a statement.
No one has so far claimed responsibility for the bombing but officials blame the Islamic State group, which considers Shiites to be heretics and frequently targets them, attacking their mosques, schools and cultural centers.
As family members and relatives were burying the victims in a mass grave on a hill overlooking Kabul, a group of armed men launched an attack on a training facility used by the country's intelligence agency in a different part of the city. In the past two years, there were at least 13 attacks on the Shiite community in Kabul alone, he said.
Early on Wednesday, the Taliban attacked a checkpoint in Baghlan, in northern Afghanistan, killing at least 30 police officers and soldiers, the AP says.
The UN has warned that as many as 150 civilians may have also been killed. Taliban had launched an attack last Friday and managed to make their way to the city center.
"It took Afghan forces - assisted by USA advisors - five days to repel the insurgents", NPR's Diaa Hadid reports.
The Afghan news site Pajhwok reported that 70 security personnel have been under siege in central Uruzgan province's Dehraud district for the past 20 days and likely were to surrender to the Taliban if they did not receive help urgently.
At least 35 Ghazni civilians have been killed, said Arif Noori, a spokesman for the provincial governor. Confusion about the death toll arose Wednesday as Kabul hospitals and government officials struggled to cope with the carnage.
Hundreds of people have fled the fighting in Ghazni, which has also killed about 100 members of the Afghan security forces. He said three Afghan security personal were also wounded in cleanup operations but no civilians were harmed.
Nearly simultaneously, a group of armed Taliban stormed a police check post near Qalat city in Zabul province, killing several policemen.
Afghanistan is littered with unexploded ordnance left by decades of war.