British criminals are forging links with East European gangsters to establish international networks for human trafficking, The Times has learnt.

Investigators believe that the number of women and children trafficked into Britain for sexual exploitation far exceeds the figure of 4,000 a year cited by the Home Office.

They are tracking gangs across Europe that have seized on large-scale migration to make multimillion-pound profits by trading in people.

“There is new evidence of British criminal involvement in trafficking,” a source said. “Some are involved in the drug trade and it’s no surprise that they are diversifying because there are huge amounts of money to be made.”

Police forces, the Serious and Organised Crime Agency and the UK Human Trafficking Centre are working with European law enforcement agencies. The same organisations were involved in the launch yesterday of Pentameter 2, the first police operation to span the British Isles.

The 55 British police forces plus the Garda Siochana in the Republic of Ireland and organisations as diverse as HM Customs & Revenue and the Poppy Project charity will work together against trafficking.

Jacqui Smith, the Home Secretary, said that the initiative was a concerted effort to combat “an appalling and devastating crime which destroys the lives of its victims”. She added: “This is a national operation to identify, disrupt and bring to justice those involved in human trafficking.”

But she ruled out any immediate move to criminalise men who used brothels and said that she could not guarantee that women who were freed from brothels would not be deported.

Police said that three trafficked women had been rescued from brothels since the operation began on Monday. The Times revealed last week that sex trafficking had spread into towns across Britain. Cambridgeshire police have raided 80 brothels this year.

The Home Office has provided an extra £100,000 to the Poppy Project, which helps to care for trafficking victims. A victim identification scheme is being piloted and there is increasing cooperation between European governments, led by Britain and Poland.

Tim Brain, Chief Constable of Gloucestershire and Gold Commander for Pentameter 2, said that it was apt that the campaign was being launched in the year marking the 200th anniversary of the Act to abolish slavery. He said: “Slavery still exists. Individuals are still being brought into this country, moved across borders against their will and being forced into servitude. Pentameter 2 aims to discover the extent of the issue and put in place whatever means available to prevent anyone else falling victim.”

Denise Marshall, of the Poppy Project, said that her charity had helped 722 trafficking victims aged from 14 to 50. One was a 19-year-old woman with a mental age of seven who had been held in a brothel in Tottenham, North London, for two years.

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