Immigration Minister Scott Morrison confirmed four asylum seekers were taken to hospital on Monday with broken bones and a wrist injury, sustained during a bloody confrontation with the security company on the island. Another two asylum seekers were injured in the violence but were treated on the island.

The violence unfolded hours after Mr Morrison told the media in Canberra that he was monitoring the situation carefully and it was ''contained''.

But shortly after midday, dozens were injured as Serco's emergency response team took to ''negotiation'' with ''non-compliant'' asylum seekers who were protesting.

''ERT were called in to assist with managing the situation and all detainees were provided with the opportunity to return to their compounds,'' Mr Morrison said.

''Four detainees were taken to hospital for a range of injuries including suspected sprains or broken bones.''

Greens immigration spokeswoman Sarah Hanson-Young said the reports were distressing.

''There are workers inside the centre afraid of what happened next,'' she said. ''The minister cannot continue to ignore these warning signs.''

Senator Hanson-Young said the ''peaceful protests'' had started a week ago in response to the government's handling of what happened on Manus Island and to mark the 100th day since asylum seeker Reza Barati's death.

Refugee advocates say witnesses described a gruesome scene on the island where asylum seekers' faces and shirts were covered in blood.

''They went in and they have been pretty brutal from all accounts,'' advocate Pamela Curr said. ''They bashed men with batons. The men have injuries on their hands and arms from trying to shield their faces.''

On Monday, advocate Ian Rintoul said 75 asylum seekers had been on a hunger strike since last Tuesday and had been joined by another 300 people. He said seven asylum seekers had stitched their lips.

Mr Morrison responded on Monday: ''The reports of the size of this protest are wildly exaggerated, which is not uncommon when advocates take it upon themselves to talk up these issues.''