The body of Farkhunda, 27, who was lynched on Thursday by an angry crowd in central Kabul, was carried to the graveyard by women amid crowds of men, a rare act of protest in a male-dominated society.
The crowd, shouting “Allah o Akbar” (God is the greatest), demanded the government bring the killers to justice.
“This is a crime against this family, a crime against a sister and a crime against humanity,” said Bari Salam, a human rights activist.
“All those involved and all those who supported her killing should be brought to justice,” he said.
The lynching ─ which took place in full view of several police officers ─ sparked widespread condemnation at home and abroad.
The United Nations said Farkhunda had “suffered mental illness for many years”.
But Farkhunda’s father said his daughter had a diploma in Islamic studies and could recite the Quran by heart. He insisted she was not involved in burning the holy book.
Farkhunda’s brother, Najeebullah Malikzada, supported his father’s claim.
“Farkhunda was a deeply religious girl. She used to recite the Holy Quran and pray five times a day,” he told the crowd.
Footage of the attack on social media shows a number of uniformed police officials watching the crowd as they beat Farkhunda to death, burn her body and then dump it into a river.
“This brutal act once again shows the incompetence of the police force,” Mariam Mustafawi, one of those at the burial said.
“Today our police force is unable to enforce the rule of law. How can they protect us against the enemy?”
Afghan President Ashraf Ghani condemned the killing as “heinous” and ordered a commission to investigate the incident.
He said police, who play a crucial part in the war against Taliban insurgents, were not well-trained to contain such incidents.
“Almost 90 percent of the duties of the police today are focused on fighting, which is not their constitutional role, it is not their legal role,” Ghani told reporters on Saturday.
“Focusing on civilian capabilities, on enforcement of the rule of law, is key to us.” Police said they had arrested 21 people, including eight policemen.
“I will question the police… we have started our inquiry. Even If I get killed, I won’t let any of her perpetrators get away with it,” said General Zahir, head of criminal investigation at the Afghan interior ministry.
Allegations of Quran burnings have sparked incidents before in the deeply conservative religious nation.
In 2012, revelation that copies of the Quran had been burnt at the US-run Bagram prison sparked five days of violent anti-US riots and attacks across the country, in which 30 people died.