Several leading charities today criticised plans to shut down a police unit dedicated to tackling human trafficking.
They have written to Metropolitan Police Commissioner Sir Paul Stephenson warning that disbanding his force's specialist team of officers would be a major blow to the fight against human trafficking.
Under the proposals, the trafficking unit's work would be passed on to the force's Clubs and Vice squad.
The charities, which include the NSPCC, Amnesty International, End Child Prostitution and Trafficking and the Poppy Project, say that specialist policing is needed to help victims who are trafficked for a variety reasons, including sex, forced labour, and domestic servitude.
In their letter, seen by the BBC, they say: "Human trafficking is a complex, sensitive issue.
"Given the continually evolving nature of the crime, it has taken the Human Trafficking Team and Non-Governmental Organisations working in the field a number of years to develop their expertise in the area.
"Policing trafficking for forced labour, domestic servitude and all other forms of exploitation requires specialist knowledge and understanding of trafficking, dedicated resources and commitment."
The charities also warned of a likely increase in the number of people trafficked into the UK in the run-up to the 2012 Olympics.
A statement from the Metropolitan Police read: "The Metropolitan Police Service (MPS) has been conducting a review about our response to all organised immigration crime and trafficking.
"That review has not concluded but proposals have been shared with partners about a potential future operational response.
"This has yet to be ratified by the MPS Management Board but proposes that Clubs and Vice have enhanced resources and take over trafficking for sexual exploitation investigations from the Specialist Crime Directorate.
"They already have expertise in this area so it will be an extension of work they are already conducting.
"The review also proposes improved intelligence and co-ordination across all areas of trafficking and organised immigration crime."