IS has claimed responsibility for a suicide attack in the Afghan capital of Kabul which officials say killed at least 41 people, but locals say 80 were killed.
The number of people killed in a bomb attack on a Shi'ite cultural centre in Kabul is double the official death toll reported by the Afghan government, witnesses and family members claim.
A suicide bombing and two minor explosions at the Tabian centre in western Kabul on Thursday left 41 dead and 84 injured, according to Afghan public health ministry spokesman Wahidullah Majroh.
The Islamic State militia said it carried out the attack.
Disputing the official death toll, Mohammad Amin, who lost his cousin in the attack, said: "Above 80 people were killed."
Amin said that the bomber detonated his explosive vest inside the basement hall, where more than 100 people, most of them students, had gathered for a graduation ceremony.
"Burnt and fragmented body parts were scattered everywhere in the hall, like in horror movies," the witness said. "I could smell the smoke and blood till midnight."
Mohammad Ali, a representative of the area, also claims that the number of those killed in the attack is higher than the government says.
Ali said almost all of those inside the hall were killed by the first explosion; others who were still alive "died while being taken out of the basement or on the way to hospitals."
Islamic State, a Sunni extremist group, considers Shi'ites as heretics and has recently increased attacks against Shi'ites, especially in the Afghan capital.
In October, 71 people were killed and 90 others were injured in an bombing carried out by the extremists on a Shiite mosque.