The former attorney-general of Papua New Guinea has called for Australia to help investigate the police shooting at student protesters that left as many as a dozen wounded. 
Kerenga Kua told Fairfax Media from Port Moresby that police armed with automatic weapons had fired directly at the students on Wednesday after they attempted to march to the Parliament.
Mr Kua said the police response was "complete overkill and completely unjustified". A hospital in Port Moresby said three students remained in intensive care with gunshot wounds.
The students have mounted a five-week boycott of classes, demanding PNG Prime Minister Peter O'Neill stand aside to face a corruption inquiry.
The students had wanted to march in support of a no-confidence motion in Mr O'Neill's government.
About 70 Australian Federal Police are based in PNG in mentoring roles and Prime Minister Malcolm Turnbull offered Australian assistance in the aftermath of the police shooting.
Several international organisations - including Transparency International and Human Rights Watch - have also called for an independent investigation into the shooting. But Mr O'Neill has said it is an internal matter for PNG and that students had provoked police by throwing stones. He said police fired warning shots into the air. Mr Kua said the student behaviour had been "exemplary" but said Australia could help secure forensic evidence for an investigation.
"Everyone is pointing fingers at each other and we need to get to the bottom of what happened," he said.
Mr Kua was sacked as attorney-general in 2014 shortly after anti-corruption police issued an arrest warrant for Mr O'Neill to face questions over millions of dollars in suspected fraud. But Mr O'Neill won a stay on the arrest warrant and the anti-corruption task force was disbanded.
The turmoil in PNG looks set to continue despite a court order on Thursday banning further protests and the government insisting classes will resume on Tuesday.
"The students definitely won't be going to class after what has happened," David Pepson, 21, a law student at the University of PNG, told Fairfax Media.
"We are shocked that the policemen opened fire on us for no reason. We can't believe how much our democratic rights and freedoms are being suppressed."
Opposition MPs are attempting to get a court order to resume Parliament and vote on the no-confidence motion. Parliament was called off after the shooting and will not sit again until   August, effectively triggering a constitutional ban on no-confidence motions, which cannot be tabled within 12 months of an election. PNG is due to go to the polls in   July 2017.