Three men have been charged as part of the slavery probe known as Operation Imperial.

Thomas Doran, Daniel Doran and David Daniel Doran have been charged with false imprisonment, conspiracy to hold a person in servitude and conspiracy to require a person to perform forced or compulsory labour.

Thomas Doran has also been charged with kidnapping.

The three are due to appear at Cwmbran Magistrates Court this morning.

The 42-year-old woman arrested on Monday has been bailed pending further enquiries.

Three men from the St Bride's area arrested on Tuesday on suspicion of slavery and servitude offences are in police custody assisting officers with their enquiries.

Detective Superintendent Paul Griffiths said: "While this is a welcome development, this fast moving investigation continues and officers remain at the site in the Marshfield area.

"Again I would appeal for anyone who may have any information which could be of assistance to contact the Police on 101 quoting log 66 23/09/13 or Crimestoppers anonymously on 0800 555 111."

Catrin Evans, Head of Complex Casework Unit, CPS Cymru-Wales, said: "The Crown Prosecution Service has been working alongside Gwent Police as their investigations under Operation Imperial, an anti-slavery operation set up to investigate allegations of mistreatment, have progressed.

"In particular, we have been offering advice and guidance to the police since four suspects were arrested on Monday.

"I have now carried out a review of the evidence gathered by Gwent Police in relation to three of these suspects.

"My review has been carried out under the threshold test of the Code for Crown Prosecutors. My conclusion is that there is sufficient evidence to charge Thomas Doran, Daniel Doran and David Daniel Doran with false imprisonment, conspiracy to hold a person in servitude and conspiracy to require a person to perform forced or compulsory labour.

"In addition, there is sufficient evidence to charge Thomas Doran with kidnapping by fraud. In respect of each of these offences, I have also concluded that charges are in the public interest.

"Accordingly, I have authorised Gwent Police to charge the three defendants and they will appear before Magistrates on Thursday.

"May I remind all concerned that these three defendants retain the right to a fair trial and police investigations into these matters are ongoing.

"While public interest in Operation Imperial has, understandably, been considerable, I would ask that nothing is placed in the public domain which could ultimately undermine the criminal justice process."