A suicide bomb attack at a voter registration centre in the Afghan capital Kabul has killed at least 57 people, officials say.
The dead include 21 women and five children, killed when the blast hit the queue outside. A further 119 people were injured.
The Islamic State group (IS) said it had carried out the attack.
Voter registration began this month for legislative elections which are due to take place in October.
IS's mouthpiece said a suicide bomber wearing an explosive belt had targeted the centre, which is in the Dashte Barchi area of western Kabul.
What happened on Sunday?
Dashte Barchi is heavily populated by members of Afghanistan's Shia Muslim minority, who have been targeted by IS for their religion in the past.
Children were standing in line with their parents waiting to register when the bomb went off on Sunday morning.
There were no immediate details of how the bomb was detonated by the attacker but the force of the blast also destroyed cars.
"I found myself covered in blood, with dead people - women and children - around me," Rasuli, 26, recalled when he spoke to AFP news agency from his hospital bed in the city.
"They all wanted to vote," he added.
Passport-sized photos and forms littered the blast site along with broken glass and pools of blood.
Another wounded man, who wept as he spoke from his hospital bed, told local channel Ariana TV, "I don't know where my daughters are. God damn the attackers!"
The same channel, Reuters news agency reports, showed angry crowds shouting "Death to the government!" and, before the IS claim of responsibility, "Death to the Taliban!"
Why are voters being targeted?
There have already been at least four attacks on such centres since voter registration got under way a week ago.
The legislative elections later this year will be followed by a presidential poll in 2019.
BBC research earlier this year found that the Afghan government had full control over just 30% of the country, with the rest of the country under significant threat from the Taliban, and, to a lesser extent, IS.
Afghanistan's interior minister told the BBC earlier this year that both IS and the Taliban were targeting civilians to provoke people against the government and create chaos.
Sunday's attack was Kabul's deadliest since at least 100 people were killed in a district full of government buildings and embassies in January.
Recent major attacks in Afghanistan
- 23 March: A car bomb in Helmand province kills at least 13 spectators at a wrestling match
- 21 March: A suspected IS suicide bomb attack near a shrine in Kabul kills at least 31 people celebrating Persian New Year
- 10 March: A Taliban attack in the western province of Farah kills 24 soldiers
- 27 January: Taliban militants drive an ambulance laden with explosives into a Kabul secure zone, killing at least 100
- 20 January: Taliban gunmen kill at least 22 people at a major Kabul hotel