A suicide bomber blew himself up in front of Kabul University on Wednesday, killing at least eight people, officials said, as Afghans celebrate the Persian new year holiday.
Another 20 people were wounded in the blast, health ministry spokesman Waheed Majroh told AFP.
A suicide attacker on foot detonated himself in front of Kabul University, the interior ministry said.
A man who was standing metres from where the explosion happened told Tolo News that he saw "at least four bodies in blood" on the ground.
The Afghan capital had ramped up security ahead of Nawrooz, which is the traditional Persian new year holiday, in anticipation of attacks.
There was no immediate claim of responsibility for the assault but Taliban and Islamic State militants have increasingly targeted the war-weary city in recent months.