Several other attacks against the ethnic group in recent years have been attributed to the Islamic State, touching off large protests in Kabul by Hazaras, who say too little is done to protect them and destabilising the Ghani government.

"Suicide attacks are a part of our daily life that we see but can't do anything about," said Hayad, who uses only one name, and is a resident of the Hazara neighbourhood where the explosion took place. "The situation is critical and the government sleeps."

The most lethal suicide bombing against Hazaras came in 2016, killing more than 80 people. The Islamic State claimed responsibility for that attack and for subsequent strikes on Shiite mosques.

But Nasrat Rahimi, a deputy spokesman for the Interior Ministry, attributed Friday's attack to the Haqqani network, which has carried out several deadly attacks in Afghanistan over the years. The Taliban denied it was responsible.

A security guard, Ali Reza, said he saw the suicide attacker walk into a line of Hazaras waiting to enter a mosque complex for a ceremony commemorating a revered leader, Abdul Ali Mazari.

The attacker set off his explosives before passing through a police screening post, suggesting that he may have triggered the bomb after a policeman spotted it. Rahim said three policemen were killed.

New York Times