A large number of students of the Punjab College of Commerce had come to witness the concert at Alhamra Cultural Complex.
The stampede occurred when private security guards used batons to push back a group of girls who rushed towards Aslam to get his autograph, police said.
"When the concert ended, some girls rushed towards Mr Aslam to get his autograph. To save Mr Aslam from the crowd, the security guards resorted to a light baton charge which caused panic among the girls," Deputy Inspector General of Police Ghulam Mahmood Doga quoting a witness as saying.
Dogar told PTI that the students then rushed to the exit, where the stampede occurred.
A large number of students were injured or fell unconscious.
The injured were taken to nearby hospitals, where doctors declared three female business students dead, Dogar said.
Officials described the condition of five injured persons as critical.
Punjab Chief Minister Shahbaz Sharif ordered an inquiry into the incident.
The Punjab College of Commerce is owned by Dunya TV chief executive Mian Amer Mahmood.
"The media is down playing the incident because the college is owned by a major media group," said a senior police officer who did not want to be named.
The mother of one of the students who died, speaking on condition of anonymity, said: "There was sheer mismanagement by the college administration. The administration has taken the life of my daughter."
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