The death toll in a suicide attack on a classroom in Kabul has risen to 35, the United Nations said on Saturday, as Hazara Shia women who bore the brunt of the attack staged a defiant protest at the “genocide” of their minority community .

On Friday, a suicide bomber blew himself up in a classroom in Kabul as hundreds of students in the Dasht-e-Barchi district took tests to prepare for university entrance exams.

The western neighborhood is a predominantly Shia Muslim enclave and home to the minority Hazara community – a historically oppressed group that has been the target of some of Afghanistan’s most brutal attacks in recent years.

“The latest casualty figures from the attack are at least 35 dead and another 82 wounded,” the United Nations Assistance Mission in Afghanistan (UNAMA) said in a statement.

The UN mission’s casualty toll is much higher than the death toll given by Kabul police – they said 20 people were killed and 27 injured in the attack on the Kaaj Higher Educational Centre.

Security has been a sensitive issue for the Taliban since returning to power last August, and the hardliners have often sought to downplay attacks that challenge their regime.

Meanwhile, dozens of Hazara women defied a Taliban ban on rallies on Saturday to protest the recent bloodshed in their community.

Around 50 women chanted, “Stop the Hazara genocide, it is not a crime to be Shia” as they marched past a hospital in Dasht-e-Barchi where several victims of the attack were being treated.

The protesters, dressed in black headscarves and headscarves, carried banners that read: “Stop killing Hazaras,” an AFP correspondent reported.

Witnesses told AFP that the suicide bomber detonated in the women’s section of the single-sex study hall.

“Yesterday’s attack was aimed at the Hazaras and Hazara girls,” protester Farzana Ahmadi, 19, told AFP.

“We demand an end to this genocide. We staged the protest to demand our rights.”

Demonstrators later gathered outside the hospital and chanted slogans while dozens of heavily armed Taliban, some carrying rocket-propelled grenade launchers, stood guard.

Since the hard-line Taliban returned to power, women’s protests have become risky as scores of protesters have been arrested and rallies dispersed by Taliban troops who fired shots in the air.

No group has claimed responsibility for Friday’s attack.

But the jihadist group Islamic State (IS) considers Shia heretics and has previously claimed attacks on girls, schools and mosques in the area.

The Taliban also view the Hazara community as pagans, and human rights groups have often accused the Islamists of targeting them during their 20-year insurgency against the former US-backed government.

Since returning to power, the Taliban have pledged to protect minorities and address security threats.

However, Amnesty International said Friday’s attack was “a shamed reminder of the inability and utter failure of the Taliban as de facto authorities to protect the people of Afghanistan”.

In May last year, before the Taliban returned to power, at least 85 people – mostly girls – were killed and around 300 injured when three bombs went off near their school in Dasht-e-Barchi.

Again, no group claimed responsibility, but a year earlier, IS claimed to have carried out a suicide attack on an education center in the same area, killing 24 people.

ISIS has emerged as a key security challenge for the Taliban, but officials claim their forces have defeated the jihadists.