Forty-eight people have been killed and 67 injured in a bomb explosion at an education centre in Afghanistan’s capital, Kabul, the country’s health ministry says.
Police say a suicide bomber walked into the centre while teaching was under way and detonated his bomb belt.
Many of those killed are believed to be teenagers who were getting extra tuition as they prepared for university entrance exams.
The Taliban has denied involvement.
This latest attack came hours after the Taliban said it could no longer guarantee safe passage for Red Cross staff working in Afghanistan, amid a row over the treatment of Taliban prisoners in a jail in Kabul.
The attack on the education centre took place in a mostly Shia neighbourhood of Kabul.
The Shia Muslim community in Afghanistan has been repeatedly targeted by Sunni Muslim extremists of the Islamic State group, which views the Shia practice of Islam as heretical.
“We can confirm the attack was caused by a suicide bomber on foot. The bomber detonated himself inside the education centre,” police spokesman Hashmat Stanikzai was quoted as saying by AFP news agency.
Meanwhile, local officials said at least nine policemen and 35 soldiers were killed in an attack on a military outpost in the northern province of Baghlan early on Wednesday morning.
Afghanistan has seen a recent upsurge in militant violence, including a major Taliban assault on the eastern city of Ghazni.
At least 100 members of the security forces were killed in the fighting at Ghazni, officials have said, with unconfirmed reports that dozens of civilians also died.