Two groups clashed following a minor dispute and series of arguments over an incident that took place on Friday at the varsity's Maulana Azad Library.
Studsents set three vehicles on fire near VC Lodge.
Police rushed to the university and fired few rounds in air to control the situation. In the firing two students sustained bullet injuries.
Despite attempts by the police, the violence did not die down till 2 a.m.
Two people, expelled ex-student Mehtab, resident of Ghazipur and Mohammad Waqif, also got injured in the firing.
"The reason behind the clash is not yet established. We are investigating the matter," said Deputy Proctor Masood.
Fire engine arrived on the scene of arson and brought the blaze under control.
According to sources, students from Sambhal, Azamgarh and Ghazipur were involved in the clash.
After the incident uncertainty clouds the B-Tech entrance test on AMU which is to be held on Sunday.
However, Rahat Abrar, the public relations officer, said that the exam will take place as per schedule.