Europe's first dedicated centre to tackle gangs who bring young women from abroad -- notably from Asia and eastern Europe -- and force them to work as prostitutes was to be opened in Britain Tuesday.
The United Kingdom Human Trafficking Centre (UKHTC) in Sheffield, northern England will also deal with those smuggled into Britain to work.
South Yorkshire Police will run the facility with specially-trained officers, lawyers and immigration workers, continuing a country-wide operation launched earlier this year to tackle exploitation in the sex trade.
Operation Pentameter involves all 55 police forces in England, Wales, Scotland, Northern Ireland and the Channel Islands, immigration and intelligence officials, prosecutors and charities.
Since its launch on February 21 this year, 188 women -- most of them aged 18 to 25 but some as young as 14 -- were rescued in raids on brothels, massage parlours and private homes. Eighty-four were confirmed as trafficking victims.
The women came from as far afield as Brazil, China, Czech Republic, Estonia, Germany, India, Iran, Jamaica, Kenya, Kosovo, Latvia, Lithuania, Malaysia, Namibia, Poland, Rwanda, Romania, Russia, Slovakia and Thailand.
A total of 232 people have been arrested, and 134 people have since been charged, according to an Association of Chief Police Officers report in July.
"Less than 10 percent of the UK's massage parlours and brothels were visited during Pentameter. It is therefore estimated that several thousand more victims remain to be found.
"Operation Pentameter is the mere tip of the iceberg," the report said.