The explosion took place as a number of students were waiting to sit an exam at Afghanistan's oldest and largest university. At least eight people were killed and 33 were injured.
A powerful bomb exploded outside the gates of Kabul University in the Afghan capital on Friday, police said.
The blast killed at least eight people and wounded another 33, according to officials.
The Taliban quickly denied responsibility for the incident. However, both they and an affiliate of the "Islamic State" (IS) group have carried out devastating attacks in the city in recent months.
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There was initial confusion over whether a suicide bomber had struck or whether the explosion was remotely detonated.
Later, an Interior Ministry official said the blast had been caused by a sticky bomb — where explosives are placed under vehicles.
Kabul Police chief spokesman Ferdous Faramarz says two vehicles were ablaze.
Second bomb defused
Faramarz added that a police team defused a second bomb that was placed close to the blast site.
A student said the explosion happened when a number of students were waiting near the campus gate to attend an exam.
The university compound houses many students over the summer, who attend classes and conduct research. The university is co-educational.
Traffic was light in the area because Friday is a weekly holiday in Afghanistan.
Despite engaging in peace talks with the international community in recent months, the Taliban continues to unleash violence in Afghanistan.
Earlier this month, the group claimed responsibility for a gun and bomb attack on Kabul's Wazi Akbar Khan neighborhood that killed at least 45 people. Officials said 116 civilians were wounded.
A previous blast close to the university last March killed at least 29 people.
mm/amp (AP, Reuters)