A large operation to tackle human trafficking, the fastest growing form of organised crime in Britain, will begin next month.

Jacqui Smith, the Home Secretary, has instructed police forces and the Serious and Organised Crime Agency (Soca) to make the fight against trafficking a priority, The Times has learnt.

Thousands of women and children are being sold into modern-day slavery in the sex industry, forced labour and street robbery by criminal gangs that have exploited the surge in immigration from Eastern Europe to extend their activities to Britain.

Even as Ms Smith prepared to announce the nationwide operation, codenamed Pentameter 2, however, she came under fire from police chiefs, who said that the Government had not recognised the criminal challenges posed by large-scale migration.

Julie Spence, the Chief Constable of Cambridgeshire, made an attack on “London-centred politicians” who relied on outdated census figures to make decisions about police funding. Ms Spence’s force is demanding an extra £2.7 million to help it to tackle a sharp growth in crime committed by foreign nationals, many of them from Lithuania.

Cambridgeshire’s new crimewave includes human trafficking, which is now seen nationally as second only to the drug trade in its potential to endanger lives. The threat posed by trafficking gangs is so serious that Soca is already gearing up to devote a quarter of all its resources to fighting them. Meanwhile, The Times has learnt that:

— More than 10,000 women from Eastern Europe, Africa and the Far East have been sold to gangs at auction for an average of £2,500 and forced into sex slavery in British brothels;

— Groups of Romanian children are being smuggled into the country and forced to earn their keep as pickpockets in Central London;

— Unknown numbers of men and women, many from Asia, are enslaved as bonded labour to pay off debts of up to £10,000 to the criminal syndicates that smuggled them into Britain; Ms Spence, who has produced a detailed report on the impact of demo-graphic change on policing in her county, said that the Government was out of touch with what was happening. She said that Cambridgeshire was treated as a rural area but it had a rapidly growing population that spoke more than 100 languages. Her force’s bill for interpreters had risen from £224,000 to £805,000 in four years.

She denied claims that she was singling out migrant workers for criticism and said that she was concerned about her force’s ability to respond to radical population change. “We have been short-changed for a number of years, losing money as the population continues to grow,” she said. “The profile of the county has changed dramatically and this simply is not taken into account.”

The force is in the midst of a major antitrafficking operation in which officers have rescued six women from brothels. A spokesman said that the women had been lured to Britain by the promise of a good job. On arrival their passports were stolen and they were sold to gangs, and forced to have sex with 25 or 30 men each day. One of the women said that she had suffered a broken back in a beating. Detectives believe that there are about 100 brothels in Cambridgeshire where women are held in sexual slavery.

Senior officers from other forces supported Ms Spence. Peter Davies, Assistant Chief Constable of Lincolnshire, said: “The big issue for us is the overall population growth, not just foreign migrants. Our figures show that foreign nationals are offenders and victims of crime in proportion to their presence in the county.”

Liam Byrne, the Immigration Minister, said: “Cambridgeshire has had something like a 20 per cent boost in their funding in real terms over the last decade, and actually crime in Cambridgeshire is down. . . so I think we have just got to be quite careful about singling out any particular section of society and pinning the blame for crime on them.”

The Association of Chief Police Officers called last night for an urgent debate about the impact of immigration on criminal activity and their ability to tackle it. A spokesman said: “It is unhealthy if people feel that they cannot talk about immigration for fear of being labelled racist.”

— Sixteen members of a gang that was smuggling Indian migrants into Britain were arrested yesterday in an operation by Belgian police.

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