Asian sex workers are being shuttled between mining towns in Australia, often against their will, according to local reports citing police.
Most of the sex workers were being exploited by criminal organizations, the police district Inspector of the inland city of Mt Isa, Paul Biggin, told The Australian newspaper.
Business was so good that the young women were being advertised in local newspapers by their handlers in what amounted to forced prostitution.
"They are working on a fly-in, fly-out [FIFO] basis, two weeks here, two weeks in the next town and so on; they are being advertised as available in the local newspapers, and they are coerced or threatened into doing it," he reportedly said.
"They are being told they cannot go to the police because in the countries they come from, the police might even be part of the problem.
"Threats are being made against their families. And whenever we have an operation to target them, they come into the station and you can see that they are being controlled mentally and physically and it's very difficult to get them to open up to authority and enable us to help them."
Mount Isa Mines is one of the biggest in the northeast state of Queensland, and has been operating for nearly 90 years, according to Australia's ABC.
The mining sector in Australia can offer workers — mainly men — huge salaries based on their willingness to work in remote areas of the country on FIFO contracts.
Such workers live for weeks away from their regular homes, either in towns near the mining operations or in camps provided by the mining companies.
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Biggin was speaking out about the issue after being awarded the Donald Mackay Churchill Fellowship, aimed at halting the trafficking of women for sexual servitude, the Australian Associated Press reported.
He was due to travel overseas to learn from other police forces attempting to combat human trafficking and the sex trade.
The ABC quoted Biggin as saying most of the prostitutes originated in nearby Southeast Asian nations, where they came from impoverished backgrounds.
"A lot of these young women, they are vulnerable, they have very poor education, they're putting a lot of pressure on legalized brothels in Queensland," he reportedly said.
"A lot of the time women are arriving legally, they are arriving here on visas that enable them to be in the country.
"It's then when they're working illegally, or being controlled through, organized crime."
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