to the hospital."

Mr Morrison said the person was injured outside the centre.

The asylum seeker who is listed as critically injured received a skull fracture and one seriously injured asylum seeker was shot in the buttock.

Both are being transferred to Australia for treatment.

The Minister said the majority of asylum seekers were not involved in the riot and were evacuated to a nearby oval for their safety. Non-essential staff were also moved out of the centre.

He said it was possible some asylum seekers were still missing.

"We're still not in a position to have accounted for every transferee which is in that centre and I hope to provide further information on that today," he said.

The Minister described the situation, which he says was brought under control at 3am (local time), as"very tense and very stressful".

"The news of a death is a great tragedy and our sympathies are extended to the transferee's - that person's family and friends who would have been in the facility as well," he 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."

Mr Morrison said the incident was the latest in a series of "largely peaceful" protests stretching back for weeks.

"This is a very distressing situation but it is not a situation, sadly, that was not anticipated," he said.

"The Government has been taking steps over recent weeks to increase our security presence at that centre."

He said the Government had learnt