The country’s police commissioner said nearly two dozen people were injured, but denied reports that as many as four people were killed.
Students in the South Pacific nation have been demanding for weeks that prime minister Peter O’Neill resign because of alleged corruption and mismanagement.
Australian Foreign Minister, Julie Bishop, said she had been advised by the Australian embassy that police shot students in Port Moresby, the capital, as hundreds prepared to march from the University of Papua New Guinea to Parliament.
“I know that students have been shot, but we’re still trying to determine whether there have been deaths and how many have been injured,” Ms Bishop said.
“We call on all sides to be calm and to de-escalate the tension and certainly call on all sides to respect the peaceful and lawful right to protest.”
Australian Broadcasting Corp reported that a Papua New Guinea politician told Parliament that four students had been killed and seven wounded.
Papua New Guinea police commissioner, Gari Baki, however, said no deaths had been reported. In a statement, Baki said 23 people believed to be university students were treated at hospitals after the clash. The head of the emergency ward at Port Moresby General Hospital told police that five of the students were in critical condition, Baki said.
O’Neill issued a statement saying he was told that a small group of students became violent, threw rocks at police and “provoked a response that came in the form of tear gas and warning shots.”
But Staycey Yalo, a journalism student at the university, said police did not fire warning shots - they fired directly at the students.
“They threw tear gas and amidst the smoke, they started shooting directly at the students,” Ms Yalo said.
“That’s when we all ran.”