Four men questioned over slavery and kidnap charges
Four people remain in custody after being arrested on slavery and kidnap charges spanning a period of 26 years.
Homes in the Rumney area of Cardiff and Bristol were raided by police on Monday morning.
Four men from Rumney, aged 57, 37, 34 and 33, are being held at Ystrad Mynach police station.
The alleged slavery offences relate to two men, who police said were safe and being supported by officers.
Three men - aged 57, 37 and 33 - were held on suspicion of knowingly or conspiring to hold a person in slavery, servitude or requiring another person to perform forced or compulsory labour, kidnap, false imprisonment and assault.
A fourth man, 34, was arrested on suspicion of knowingly or conspiring to hold a person in slavery, servitude or requiring another person to perform forced or compulsory labour and assault.
A Gwent Police spokeswoman said the four arrests related to two alleged victims, who were not recovered from the addresses raided.
The arrests were made by officers working on Gwent Police's anti-slavery Operation Imperial.
South Wales Police and Avon and Somerset Police were also involved in Monday's operation, as warrants were executed at five addresses in the Cardiff and Bristol area.
Det Supt Paul Griffiths, who leads Operation Imperial, said: "All four arrests relate to two victims, both men, who are being supported by specially trained officers. The alleged offences we are investigating are extremely serious.
"Allegations from one of the victims cover slavery, servitude and forced labour and span a period of 26 years. Allegations from the other victim cover kidnap, false imprisonment and assault and span a lesser timeframe.
"Anyone with any information that could help is asked to call the Imperial team directly by dialling 01633 647174.
"Alternatively, if someone has information and would rather not pass this directly to the police then I would urge them to contact Crimestoppers, which is independent of the police and guarantees complete anonymity on 0800 555111."
Jacqueline Parry, a local councillor from Rumney said: "There will be absolute shock (over the arrests).
"You do not expect it in a suburban area, an area where people know each other, where there are communities."