KABUL (AFP) - Hundreds of protesters shouting "Down with ignorance!" urged the Afghan government on Tuesday to bring to justice the killers of a woman lynched by a mob for allegedly burning the Quran.

Farkhunda, 27, was beaten with sticks and stones, thrown from a roof and run over by a car outside a mosque in Kabul last Thursday.

The mob then set her body ablaze and dumped it in the Kabul river while several police officers looked on.

Demonstrators gathered in the rain outside the supreme court in Kabul, demanding justice and shouting, "Down with ignorance! We want justice for Farkhunda."

"She was our sister," said Ahmad Zia, one of the protesters.

"The people who killed her had no respect for women, for law or for Sharia. Her brutal killing should bring a big change."

Women's rights activist Soraya Parlika added: "This is the first time in Afghan history that we have witnessed such brutality. This is such an inhumane and un-Islamic act against a woman."

Some carried banners calling for the resignation of the city's police chief.

In downtown Kabul, meanwhile, residents of the Afghan capital planted a tree near the site of Farkhunda's killing to mark the brutal assault.

"I feel as if they have killed and burnt my daughter," said one tearful woman at the tree-planting.

"All those people are cowards, they should have protected her," the woman, who declined to be identified, said.

"They could have protected her if they wanted to."

Late on Tuesday, even the Afghan Taleban condemned the woman's killers for "using the Quran (as a) pretext to kill innocent humans," in a highly unusual statement.

The group also extended condolences to Farkhunda's family and warned: "We will severely punish the killers of this innocent woman to prevent such incidents from happening in future."

'HEINOUS' KILLING

The demonstration followed another protest by scores of people Monday, demanding the killers be brought to justice.

President Ashraf Ghani has condemned the killing as "heinous" and ordered an investigation into her death.

On Tuesday, a spokeswoman for European Union foreign policy chief Federica Mogherini said Farkhunda's death was "a tragic reminder of dangers women face from false accusations and the lack of justice in Afghanistan."

Interior Minister Noorul Haq Ulumi told parliament on Monday that Farkhunda had not in fact burnt a Quran.

"The accusation against her is completely invalid. Farkhunda was a religious girl, she was not involved (in burning the Quran), she was innocent," the minister said.

"It is very painful that we were not able to protect a pious young person. We hope this will not be repeated again."

His ministry said Tuesday its investigation had led to the arrest of 28 people as well as the detention and interrogation of 20 policemen following reports they did nothing to prevent the lynching.

The chief spokesman for Kabul's police force was also sacked after making comments on social media condemning the burning of the Quran, rather than the lynching.

Farkhunda's body was carried to the graveyard by women on Sunday, a break with the tradition that men should carry the coffin.

Allegations of Quran burnings have sparked violent incidents before in Afghanistan, a deeply conservative religious nation.

In 2012 the 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.