Police have arrested three men as part of an investigation into human trafficking and modern slavery in Northamptonshire.
Six other people are being supported by the Red Cross and Salvation Army following a series of swoops in Daventry.
At one car wash they found poor working conditions, unsanitary living areas and evidence staff were being paid below the minimum wage.
The trio who were detained are aged 28, 29 and 38.
All have since been bailed pending further inquiries.
If oyu need help and advice about the issue click HERE or call the helpline number 0800 0121 700
To report trafficking or slavery call police on 101 or in an emergency 999.