Seven people were arrested and 11 potential male victims of human trafficking identified as part of a joint operation involving the Gangmasters Licensing Authority in Derby. The 11 potential victims involved were working in meat processing and flower packing in the city.
Five arrests resulted on 15 July when Derbyshire police executed four warrants in the city with the assistance of the GLA and representatives from the Serious Organised Crime Agency's UK Human Trafficking Centre.
Police believe the 11 potential victims have been trafficked into the UK from Eastern Europe.
The men were taken to a special reception centre where they were cared for by Derbyshire County Council, Derby City Council, the Salvation Army and the Red Cross.
Detectives later arrested a 21-year-old man and a 41-year-old woman on suspicion of conspiracy to commit human trafficking and money laundering, taking the total to seven. All suspects remain in custody.
Officers suspect some victims' details may have been used to claim benefits fraudulently and that some of the victims may have been sent to work at different locations in the city. Detectives are working with the Department for Work and Pensions and the GLA as part of the investigation.
GLA chief executive Paul Broadbent said: "Once again I'm pleased to hear that through working closely with partner agencies we have hopefully now removed these men from a position of exploitation and played a significant part in attempting to tackle those we suspect are involved in serious criminal activity.
"Forced labour is a deeply concerning and increasing crime trend among organised crime networks and as such it remains at the very top of the GLA agenda."