Afghan interior ministry spokesman Najib Danish confirmed to that at least seven people have been killed and nine others wounded in Monday's attack. He had earlier reported the death toll was 12 people. Police officials also confirmed there were seven deaths.
"The attackers was on foot near the gate of the university," Danish told.
Waheed Majrooh, a spokesman for Afghanistan's Ministry of Public Health, told that at least 12 wounded were transfered to emergency units.
The religious scholars across the country had gathered in the tent to issue a 'fatwa' - a religious edict issued by an expert in Islamic law - against suicide bombings and the ongoing war in the country.
"The gathering had just finished and the clerics were coming out of the tent when that sucide bomber went off," she said.
"They had just come to an agreement saying that suicide bombing was unislamic."
No group immediately claimed responsibility for the attack, which underlines deteriorating security ahead of parliamentary and district council elections set for October.
Both the Taliban and the Islamic State of Iraq and the Levant (ISIL, also known as ISIS) have stepped up attacks on Kabul, making it the deadliest place in the country for civilians in recent months.
Security around Kabul has been on high alert in recent days with more checkpoints and patrols as the government warned of attacks by the Taliban on government installations.
On Wednesday, gunmen stormed the heavily fortified headquarters of the interior ministry, battling security forces for more than two hours.
In April, at least 26 people, including nine journalists were killed who had arrived to report on an initial blast and were targeted by a suicide bomber.
A week earlier, at least 57 people were killed in Kabul when a suicide bomber detonated his explosives at the doorway of an ID distribution centre in the voter registration centres.
The Taliban often claim their fight against the foreign forces and their followers in the country is a holy war. They are seeking to return the country to strict Islamic rule after their 2001 ouster by US-backed troops.
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