Raids part of EU funded project to tackle trafficking
14 May 2013 Last updated at 15:55 BST
Police in West London are carrying out raids as part of a two year EU funded project to tackle human trafficking.
In 2012 the UK National Referral Mechanism received nearly 1,200 referrals of potential victims of trafficking, an increase of 25% from 2011.
BBC Radio 5 live's reporter Lesley Ashmall was given access to the police operations.