Deadly blasts have ripped off the Aleppo University in Syria's commercial capital killing dozens of people as the death toll in the war-torn country continues to increase.

Nearly 83 casualties have been reported so far and dozens of others have been injured increasing the likelihood of a higher death toll. Many of the wounded are in critical condition according to the UK-based monitoring group Syrian Observatory for Human Rights.

The double explosion rocked the university premises while the students were sitting exams. President Bashar al-Assad's troops and the anti-regime fighters accused each other of the attack.

The victims include students at the university and also the refugees who sought shelter at the buildings due to the ongoing conflict in Aleppo.

Television images show the burnt vehicles and blast-ravaged buildings indicating the intensity of the attack. Dead bodies, which were lying scattered left the onlookers in tears.

"The warplanes of this criminal regime do not respect a mosque, a church or a university," a student who called himself Abu Tayem told Reuters.

Pro-regime Syrian state TV said "terrorists", the term which Assad uses for rebels, launched rockets at the university. On the other hand, the armed opposition groups have blamed Assad's forces of firing missiles from fighter jets at the university buildings.

"So far there are 82 fatalities and more than 160 wounded in a terrorist attack that targeted students on their first day of exams at the University of Aleppo," the governor of the city, Mohammed Wahid Akkad told the AFP.

An unconfirmed report suggests the explosion was caused by a rebels-launched missile which missed the target of striking Assad's warplane.

"A cowardly terrorist act targeted the students of Aleppo University as they sat for their mid-term examinations," said Bashar Ja'afari, the Syrian envoy to the UN.

If the regime's account of the attack gets confirmed, this will be the first time the lightly-armed rebels have carried out such a major attack.

Syria's largest city Aleppo has witnessed some of the bloodiest battles during the 22-month-long insurgency against Assad. Both pro and anti-Assad forces have been tirelessly attempting to capture the strategically important city of Aleppo which was once a thriving commercial region.

Aleppo has so far been largely controlled by Assad's forces and the nearest rebels' stronghold in the city is more than a mile away from the university.

Unverified video.