At least 22 have been killed in their classrooms after gunmen stormed a university campus in a “despicable act of terror”.
Harrowing video of the brutal attack shows students frantically running from the campus as gunfire can be heard ringing out in the background.
According to the BBC, some students could even be seen scaling the walls of the building to escape.
Officials and witnesses said gunmen barged into the university and shot at students in classrooms and those attempting to flee.
Photos shared by a senior government official showed students lying dead in classrooms, some next to their books. One student appeared to have been shot as he was climbing out of a window.
"They were shooting at every student they saw ... they even shot at the students who were running away," witness Fathullah Moradi told Reuters.
President Ashraf Ghani has called the mass shooting a “despicable act of terror” while Ghani, who once lectured at the university, announced in a video message it was a national day of mourning.
"My heart is still beating for this academic institution," he said.
"Today's attack has left us grief-stricken."
It is the second attack on the campus in the Afghan capital in just over a week.
A suicide bomber killed 24 people including teenage students at an education centre in Kabul on October 24.
Islamic State claimed responsibility for that attack, without providing evidence.
Taliban insurgents issued a statement condemning the latest attack and denying any involvement.
Violence has plagued Afghanistan while government and Taliban negotiators have been meeting in Qatar to try to broker a peace deal and as the United States brings home its troops.
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