THE PSNI has arrested four people as part of an operation targeting human trafficking.
The three men and one woman were detained following searches in Co. Antrim and Co. Tyrone on Tuesday.
The operation targeted the activities of an organised crime group suspected of trafficking Romanian women for the purpose of sexual exploitation.
"We believe the organised crime group coaxed Romanian women to travel to Northern Ireland with the false promise of a better quality of life," said Detective Inspector Rachel Miskelly.
"The shocking reality is that, upon arrival, the women have been forced into prostitution and exploited."
Further victims
Four searches, three in Ballymena and one in Omagh, were carried out by detectives from Organised Crime Branch with the support of officers from Tactical Support Group (TSG).
Three men, aged 27, 31 and 52, and a 21-year-old woman were each arrested on suspicion of human trafficking for sexual exploitation, controlling prostitution for gain, brothel keeping and money laundering.
They remain in custody at this time.
The PSNI has identified and offered safeguarding to one female victim but believe there are others yet to be identified.
"Whilst the brothels linked to this group were located in Ballymena and Omagh, we believe that victims may have been transported to various locations throughout the country for the purpose of sexual exploitation," said DI Miskelly.
"Unfortunately, we suspect there are more victims yet to be identified and our investigation will continue."
'Treated like commodities'
DI Miskelly appealed for information to help crack down on criminals exploiting those seeking a better life.
"Organised crime groups involved in human trafficking typically seek to identify, groom and exploit individuals," she said.
"They prey upon those who are in any way vulnerable.
"Victims' hopes of a better life are abruptly shattered and instead they are treated appallingly.Innocent people are treated like commodities.
"They are forced to engage in sexual activity, with money made going straight into the pockets of criminals."
She added: "We will continue to do everything in our power to tackle human trafficking for sexual exploitation, but we need your support.
"This very real issue could be happening in your street or neighbourhood. And I am appealing to you, if you have any information or concerns that someone is being exploited or controlled, to please contact us.
"Likewise, if you are, or have been, a victim please speak to us.
"We have a dedicated team who want to help you and I promise you will be treated with the utmost respect and sensitivity."