"They are attacking again." This is how Benham Satah, a witness to the murder of Reza Barati three years ago described the eruption of violence at the Manus Island detention centre on Friday night.

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.