Asylum seekers have come under attack from locals at the Manus Island detention centre, with gunshots fired and at least one person injured.
The Australian Immigration and Border Protection Department confirmed in a statement an "incident" had occurred at the detention centre.
"There are reports PNG military personnel discharged a weapon into the air during the incident," the department said.
Asylum seekers said a large group of locals tried to storm the centre at 6.30pm local time.
Australian staff were seen running for a boat moored nearby, while asylum seekers hid in their rooms as shots rang out, the ABC reported.
The department said at least one male asylum seeker was injured by a rock that had been thrown during the incident, and was receiving treatment.
They said no one was injured as a result of the gunfire.
Initial reports suggested both Papua New Guinean Police and Navy were involved in the shooting.
One detainee said the violence had erupted as locals tried to stop a soccer game involving detainees.
"Navy guys and locals I think trying to get inside the camp after beating Australian guards," he told Fairfax Media.
"Our camp is under attack. The Navy officers are firing. I am hiding in my room."
The refugees came under attack as they were leaving the field, another detainee said.
The Refugee Action Coalition said all staff had fled the compounds, leaving refugees and asylum seekers unprotected.
The refugee group said about 100 shots were fired.
The attack is the latest in a string of violent incidents at the centre, including the death of Iranian man Reza Berati, who was killed during a riot in 2014.
Greens Senator Nick McKim tweeted the news was "very disturbing".
Local police sent reinforcements to the centre during the incident.
"We have police on the ground and they are trying to contain the situation," Provincial Police Commander David Yapu told the ABC.
The Immigration Department said it was continuing to monitor the situation.