A 51-year-old man has been arrested as part of an ongoing investigation into slavery in South Gloucestershire and Bristol.
The man was arrested in South Gloucestershire on suspicion of a slavery and forced labour offence in connection with the continuing Operation Wanderer.
He was interviewed and released on bail until April 15 pending further inquiries.
Detective Superintendent Sue Scott said: “The joint investigation into forced labour and exploitation is continuing to progress and our priority remains the safeguarding and protecting of vulnerable victims.
“Following a series of warrants executed in December, three men were taken to a place of safety and entered into the National Referral Mechanism - a framework for identifying victims of human trafficking and ensuring they receive all the protection and support they need.
“If anyone has concerns about someone who they believe could be a victim of forced labour, please call us as soon as possible.”
Last December's raids at travellers' camps in Northwood Park, Winterbourne; Tall Trees, Almondsbury, and Green Orchard, Easter Compton, at a business unit and a house in South Gloucestershire and a house in Bristol led to three men in their 30s, 40s and 50s being freed from slavery.
A total of seven people were arrested at the time.
Police said anyone who could help the investigation team should call them on 101 or phone Crimestoppers anonymously on 0800 555 111.