Police in Port Moresby say they are confident an inquiry into alleged police shootings on a university campus will exonerate them.
Earlier this month, over twenty students from the University of PNG in Port Moresby were hospitalised after police opened fire on them when they attempted to march to parliament.
At least five sustained serious bullet wounds.
The students had been boycotting classes since May, demanding the Prime Minister Peter O'Neill step down and submit to an investigation into alleged fraud.
Since the shootings at the UPNG three weeks ago, tensions have been building at PNG's two other main universities in Goroka and Lae.
At the weekend, a first-year student was killed at Lae's University of Technology and buildings were burned in what the university said appeared to be a targeted attack.
As Lae police arrested three suspects today, pressure is growing on the government to respond to the rising tensions.
The government says the retired judge, Justice Warwick Andrew, will chair a Commission of Inquiry into factors around the violence.
The NCD Metropolitan police commander, Ben Turi, said he was at the campus and gave no command to shoot - he maintained the reports were exaggerated.
He said some police shot in the air outside the campus and used tear gas to disperse crowds on the streets blocking businesses.
But a student representative Hercules Jim, said it would be hard to argue against the student witnesses.
"Some students were shot on the head and on the wrists and all this, how do you expect the bullets that were shot into the sky to go into their heads and into the students?" said Mr Jim.
"The claim by the police that they have not shot the students is not true and we condemn their actions and we want to make sure there is justice served."
Hercules Jim said that due to the weekend's violence and loss of life in Lae, all protests had been stopped.
The Commission of Inquiry will look into the role of the Student Representative Council, the management of the universities, the role of police and whether there was outside influence and incitement of students.