Several detainees reported sustained gunfire from outside the centre after a local sparked an altercation when he tried to shut down a soccer game involving detainees in the Navy base that surrounds the compound.

They said Wilson Security guards who were attempting the protect asylum seekers came under sustained assault from outsiders intent on attacking the refugees.

At least one detainee, a Sudanese refugee, is understood to have been badly hurt after being hit by a rock and a gate to the centre was rammed by a car. A code red was declared and the centre placed in lock-down, detainees said.

A spokesperson for the Australian Immigration and Border Protection department confirmed an incident was being investigated by PNG authorities and that "residents" were safely inside the centre. "There are reports PNG military personnel discharged a weapon into the air during the incident. No-one was injured," the spokesperson said.

"Navy guys and locals I think trying to get inside the camp after beating Australian guards," Imran Mohammad, a 22-year-old Rohingyan refugee reported. "Our camp is under attack. The Navy officers are firing. I am hiding in my room," he told Fairfax Media.

He later said: "We are left by ourselves. There is no security inside the compounds."

Several detainees said they feared a repeat of the violence of February 2014, when scores of asylum seekers were injured and Mr Barati was killed when local security guards and residents attacked the centre after days of protests by detainees.

"The refugees were playing soccer in the field and around six o'clock the locals said to the refugees to leave the field," one detainee reported.

"They were leaving the field and suddenly the navy officers and the locals started beating the refugees."

A separate account said the officer who initiated the confrontation was drunk and was hurt in the initial fracas, prompting the officer and others to seek revenge.

"The refugees came back inside the camp now, but the Navy officers are throwing stones and now they are firing. We are really scared now. It's like another riot taking place here today."

One detainee said locals and Navy officers had filled vehicles with stones and were driving around the four compounds throwing them.

Mr Satah said he heard gunfire over a 10-minute period. There were no casualties in the Mike and Foxtrot compounds and they were waiting to establish this was the case in the Oscar and Delta compounds, which were closer to the gunfire, he said.

Late last night he had been told by security guards that asylum seekers were safe but the gates to the centre remained locked.