A TIP-OFF to the Salvation Army uncovered their ''abhorrent situation''. Three young women, allegedly lured to Australia from Thailand on the promise of student visas, had been allegedly held against their will to work as sex slaves in a Sydney brothel.

Yesterday, the Australian Federal Police announced they had arrested the 42-year-old Chinese-Cambodian owner of the Diamonds 4 Ever brothel in Guildford and charged him with human trafficking offences.

The three women, believed to be under 18, claim they were told they were travelling to Australia on student visas but, once here, their passports were confiscated and they say were taken to the brothel and forced to work as prostitutes.

The brothel's website boasts of ''dream ladies'' and an excellent reputation for luxurious, prestigious services.

But the reality was ''abhorrent'', the AFP's national co-ordinator of human trafficking operations, Glyn Lewis, said.

''It's our general experience [that] these women live under very harsh conditions,'' he said. ''Their freedom's restricted, they may be forced in various ways coercively, threatened with deportation by the owners [and] lied to. They often have [poor] language skills so they're really in a very frightened state when we get to meet them.''

Jennifer Burn, director of Anti-Slavery Australia at the University of Technology, Sydney, said a client or co-worker may have raised the alarm to the Salvation Army, which runs a safe house for victims of human trafficking.

The women chose to speak to police, leading to a long investigation culminating in late-night raids on the brothel as well as four residential and business addresses in Cabramatta, Casula and Canley Heights on Wednesday.

The brothel owner, Phnom Penh-born Song Chhoung Ea, was arrested and charged with several offences carrying a maximum of 25 years' imprisonment. The charges include conducting a business involving sexual servitude, facilitating entry of persons into Australia knowing they would be exploited and allowing persons to work knowing they were in breach of visa conditions.

The women have been referred to the Red Cross for a three-month recovery program and may be granted special witness protection visas.