A 29-year-old Briton died in an Australian immigration centre Wednesday, officials said, with refugee advocates claiming it was a suicide -- the third within as many months.
Immigration officials said the man, detained for a visa breach, was found not breathing in his high-security accommodation block in the western Sydney Villawood centre at 3:20 am and attempts to resuscitate him failed.
"Investigations into the circumstances of this incident are ongoing," an immigration spokesman told AFP.
Refugee activists said they had been told by fellow inmates that the man had taken his own life.
"This is the third death in three months at Villawood. The immigration department cannot explain this away," said Ian Rintoul from the Refugee Action Coalition.
"Something must be done to break the vicious downward spiral that has developed at Villawood."
The immigration official refused to speculate on whether the death was a suicide, saying it was now a police and coroner's investigation and "it would be inappropriate to discuss the matter further."
"The department expresses its sympathy to the family of the deceased man and will fully cooperate with the coroner," he said, adding that counselling would be provided to detainees and staff.
Two other men have died in Villawood since September, with a Fijian national jumping from a roof to his death and an Iraqi reportedly hanging himself in a bathroom.
Tensions are running high in Australia's crowded immigration centres, with rooftop demonstrations, breakouts, hunger strikes and one group even sewing their lips together in protest after the Iraqi's death last month.
Rintoul said the latest death illustrated the problems with Australia's mandatory detention policy for boatpeople and other illegal immigrants.
After experiencing an influx of such arrivals in 2010, mostly from Sri Lanka and Afghanistan, detention centres have been stretched to capacity for months.
"The government's addiction to such an authoritarian and punitive detention regime is literally costing people's lives," Rintoul said.
"How many more lives will it take before the government puts a stop to it?"