The partner of a New Zealand man who died in an Australian detention centre is calling for answers about his death.
Rob Peihopa, 42, was found unconscious by staff at the Villawood Detention Centre in Sydney just before 10pm yesterday.
Australian Department of Immigration said Mr Peihopa was found unconscious and is suspected to have suffered a heart attack, but fellow inmates claim he was viciously attacked before his death.
A report will be prepared for the New South Wales coroner, the department said.
Mr Peihopa was facing deportation to New Zealand and had been in detention for nearly 10 months after serving time for dangerous driving charges.
His Australian partner, Tracy McPherson, said he should have been allowed to return home sooner.
"Why are these people being put into these detention centres and left there to rot?
"You know, it's just not fair, they've done their time in jail. It's time to go home to your family, to your children."
Serco, which runs the centre, said there was no fight.
In a statement released this afternoon, Australian Immigration said Mr Peihopa died from an apparent heart attack.
It said staff attempted to revive him alongside ambulance personnel, but he died a short while later.
His body was laid out for a few hours to give other New Zealand detainees a chance to farewell him.
Vaelua Lagaaia, a detainee at the centre, said all of the New Zealand detainees knew him, and performed a haka before he was taken away.
"Just before they were gonna load his body up, they gave us the opportunity to have a little farewell for him.
"They also let us do a haka for him as they were taking his body away."
Mr Lagaaia said Mr Peihopa had been visiting other New Zealand detainees at a neighbouring compound, but everyone was tight-lipped about what happened.
He said his death was a shock, because he was a fit man who exercised regularly, but it could have been the stress.
"It's not easy being in here.
"A lot of people are gonna start thinking that we don't want the same thing to happen to anyone else."
Another detainee at the Serco-operated centre, Rawio Fowell, said it was not a heart attack that killed Mr Peihopa.
"If it was a heart attack, why did he have a gash on his face and two black eyes?
"Serco's only saying that it was a heart attack so they don't look bad."
He said Serco staff and several detainees told him Mr Peihopa was involved in a fight, and showed signs of being badly beaten up.
'It's a melting pot of emotions'
Another former detainee told RNZ News Mr Peihopa was attacked and beaten before he died.
Their claims were difficult to corroborate, but an advocacy group for detainees said it was not surprised.
Iwi N Aus founder Erina Morunga said all kinds of people were lumped together in detention centres.
"It's a melting pot of emotions, a melting pot of people of varying backgrounds, people aren't segregated like they are in prisons.
"If you've got different types of offenders, they get segregated don't they, especially if they are sexual offenders."
But she said that was not what happened in detention centres.
"They just get jumbled up."
Ms Morunga said Mr Peihopa's family, who lived in Sydney and visited him regularly, were in disbelief.
"Speechless, inconsolable, unable to speak right now, in shock, you know the whole situation of being detained, waiting for a decision on your life.
"Your family are doing time with you, they are also suffering."
Mr Peihopa left behind a partner and four sons, one of whom was still in New Zealand.
Mr Fowell said Mr Peihopa had been his best friend for 25 years.
"He's a gentleman, he was a staunch religious Christian, staunch about his faith.
"He's a mate that you want, you know."
He said Mr Peihopa helped him get through the loss of his wife, who died from breast cancer last October while he was in detention.
"Now he's gone, so I gotta man up, you know.
"He was someone to talk to, and someone to tell you straight how it is, not bulls**t, he was a straight shooter."
Labour MP Kelvin Davis said he had also heard reports of an altercation inside the detention centre, but he did not want to speculate whether that was the cause of death.
He said it still raised questions about why Mr Peihopa was still in detention.
"It's the whole issue about why these guys are in the detention centre when they've already served their time in prison.
"They should be allowed to go home to their families, and then if their visas are revoked, they can be sent home."
Be wary of speculation - PM
Prime Minister John Key said he did not know what the conditions were inside Villawood, but said people should be careful not to make assumptions about what happened.
"While I don't have a huge amount of information, I just caution people about jumping to conclusions about what caused the death.
"Certainly some of the claims that I've seen don't tally with the information that I've been given."
The New South Wales coroner has begun investigations into the death.