Unitech Security walked off their jobs yesterday, leaving the gate and university unmanned.
The Unitech administration sent in a formal request (in writing) last night and police went on campus this morning.
Police are on campus not to harass, intimidate or investigate anyone but to protect government property.
There are also reports from administration that some students want to attend classes but are afraid to do so.
Lae metropolitan superintendent Anthony Wagambie Jnr says he wants peace to prevail.
Students who want to attend classes can do so and those who want to stay away as a sign of protest can also do so.
He encourages students and intellectuals on campus not to take Police presence as a threat.
"They have their rights and can go ahead in a peaceful way without intimidating or harassing each other," Wagambie Jnr says.
What happened previously, where a fight broke out and an Engan student was seriously injured, was regrettable and students should not fight each other.
He stressed that police presence was requested by the administration for the benefit of all, the students as well as the staff.