At least 34 people were killed in a suicide bomb attack in front of an education centre in the west of the Afghan capital, Kabul, according to the health ministry.
Wednesday's attack in the Shia neighbourhood of Dasht-e-Barchi left dozens more injured, Waheed Majrooh, a spokesman for Afghanistan's ministry of public health, told Al Jazeera.
The health ministry previously announced the death toll as 48. It was revised to 34 on Thursday.
It was not clear how many students were at the centre - which specialises in preparing students for university exams - at the time of the attack.
The explosion initially set off gunfire from Afghan guards in the area, leading to assumptions that there were more attackers involved, but officials later said all indications were that there was only one bomber.
"We can confirm the attack was caused by a suicide bomber on foot. The bomber detonated himself inside the education centre," said Hashmat Stanikzai, police spokesman.
Abdul Hossain Hossainzada, a Shia community leader in the neighbourhood in western Kabul, said the bomber apparently targeted the course, which had young men and women studying together.
Zabihullah Mujahid, Taliban spokesman, denied involvement in the attack.
Jawad Ghawari, a member of the city's Shia clerical council, blamed the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) group, which has carried similar attacks in the past, hitting mosques, schools and cultural centres.
ISIL claimed responsibility for the attack on Thursday.
In the past two years, Ghawari said there were at least 13 attacks on the Shia community in Kabul alone.
Abdullah Khenjani, the editor-in-chief at Afghanistan's 1TV broadcaster, told Al Jazeera from Kabul: "There is a suspicion that Taliban is using ISIL's name to decrease the public pressure when it comes to these kinds of very brutal attacks on civilians, especially young children."
