UPDATE 2-One dead, many hurt as asylum seekers riot at PNG detention camp

* One asylum seeker killed, another critically injured

* Critics call for closure of detention centre

* Rights groups allege violence started by villagers, police attacking centre

(Adds allegations that locals attacked centre, G4S denial))

By Matt Siegel

SYDNEY, Feb 18 (Reuters) - An asylum seeker was killed and at least 77 injured in the second riot this week at a detention centre in Papua New Guinea used to process asylum seekers, Australia's Immigration Minister said on Tuesday.

One person was in critical condition with a head injury and another sustained gunshot wounds during the clashes on a small island in impoverished Papua New Guinea.

Immigration Minister Scott Morrison says the riot began when detainees forced their way out of the centre, but refugee advocates insist it was sparked when Manus Island residents and police stormed the facility, attacking the asylum seekers.

The facility is part of Australian Prime Minister Tony Abbott's tough stance against asylum seekers but it has come under fire over human rights concerns.

"Our sympathies are extended to the transferees - that person's family and friends who would have been in the facility as well," Immigration Minister Scott Morrison said in reference to the dead asylum seeker.

"If people choose to remove themselves from that centre then they're obviously putting themselves at much greater risk and in an environment where there is violent behaviour," he told reporters in the northern Australian city of Darwin.

Canberra's tough stance on asylum seekers, including offshore processing and a blanket ban on people arriving by boat ever settling in Australia, has been criticised by the United Nations and other groups as illegal and inhumane.

Australia uses detention centres at Manus Island and another on the tiny Pacific island of Nauru to process would-be refugees sent there after trying to get to Australia, often in unsafe boats after paying people smugglers in Indonesia.

Refugee advocates say that long-term detention, combined with a lack of clarity on where and when the asylum seekers may be resettled, contribute to a host of mental health problems at the facilities.

Last month, detainees at a centre in the remote Australian territory of Christmas Island sewed their lips together as part of a hunger strike in protest over their treatment.

The latest incident followed an attempted breakout from the Manus Island facility on Sunday night, when 35 asylum seekers briefly escaped. Nineteen were injured and eight arrested in that incident. News Search ID:nL3N0LL0QP

Refugee advocates said detainees and staff members had told them that the violence started again when Manus Island villagers armed with makeshift weapons and police stormed the facility after dark and began attacking detainees.

"Locals armed with machetes, pipes, sticks and stones - have bashed and cut asylum seekers. One asylum seeker has been thrown from the second floor of a building; others have suffered machete cuts," the Refugee Action Committee said in a statement.

The Sydney Morning Herald said it had spoken with a man whose brother is in the facility. Ghulam Murtaza told the newspaper he had received a phone call from his brother late on Monday saying villagers had come inside the compound.

"He said, 'they will kill us'. He was in the compound saying 'I am going to run away to save my life'," Murtaza said.

British outsourcing giant G4S , which is responsible for security at the facility, said villagers were not involved.

"Claims that the transferees breached the fence following internal attacks on them by local residents are unfounded," it said in a statement.

Morrison said security guards had regained control of the centre, which had not been damaged. He said it was possible some detainees were still missing.

The unrest in Papua New Guinea quickly drew calls from critics to shut the facility. The U.N. High Commissioner for Refugees had already said in a November report it failed to provide "safe and humane conditions of treatment in detention".

(Editing by Paul Tait)

((matthew.siegel@thomsonreuters.com)(+61 2 93731811)(Reuters Messaging: matthew.siegel.thomsonreuters.com@reuters.net))

Keywords: AUSTRALIA IMMIGRATION/MANUS