Thirty-five asylum-seekers broke out of the same facility on Sunday evening, with several injured, as tensions mount about their fate under the Australian government's hardline policies.
"The news of a death is a great tragedy," Immigration Minister Scott Morrison said.
"This is a tragedy but this was a very dangerous situation where people decided to protest in a very violent way and to take themselves outside the centre and place themselves at great risk."
Morrison said that despite the unrest, the immigration centre had not been destroyed.
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In an earlier statement today before he led a press conference, Morrison said some of those in the camp "breached internal and external perimeter fences".
"I am advised that all staff have been accounted for, our service providers are in control of the centre and there has been no damage to critical infrastructure or accommodation at the centre, which will enable the centre to resume normal operations."
Manus Island is one of two remote Pacific camps being used in Canberra's punitive off-shore detention policy.