KABUL: Dozens of Afghan women's rights activists took to the streets Wednesday to protest against the recent public execution of a young woman for alleged adultery, which was captured in a horrific video.

The 22-year-old victim was shot dead as dozens of men cheered in a village about 100 kilometres north of the capital Kabul.

The execution was blamed by the authorities on Taliban militants and caused global outrage, with world leaders denouncing the fundamentalists, who are waging an insurgency against the Western-backed government.

“We want justice,” the protesters, almost all women, shouted as they marched from the women's affairs ministry towards the UN headquarters in Kabul.

“The execution of the woman by the Taliban was a crime... the government must do everything to bring the culprits to justice,” parliamentarian Shinkai Karokhail, who joined the march, told AFP.

“This is the duty of the government to deliver justice.”

President Hamid Karzai condemned the killing as un-Islamic and unforgivable, while security forces have launched a manhunt for those responsible.

The commander of Nato's 130,000 troops in Afghanistan, General John Allen, offered to help local security forces track and capture the men involved in what he called “an atrocity of unspeakable cruelty”.

Public executions of alleged adulterers were common when the Taliban were in power from 1996 until 2001, when they were ousted by a US-led invasion for harbouring Al-Qaeda leader Osama bin Laden after the 9/11 attacks.