Four people have been arrested and nine female sex workers are being protected by police as part of a nationwide crackdown on human trafficking and modern slavery.

Officers visited four premises – two in Cambridge and two in Peterborough – in connection with suspected exploitation of sex workers.

It was part of Project Aidant 13, a National Crime Agency drive to identify and safeguard victims of sexual exploitation, or those who are trafficked into the UK for that purpose.

Detective Inspector Nick Skipworth said: “This operation was about safeguarding the vulnerable and tackling those who seek to exploit. We are grateful to our partners for assisting us to support some potentially vulnerable people.

“The public play a key role in helping to tackle modern slavery and labour exploitation. Suspicions relating to modern slavery and human trafficking should be reported via the Modern Slavery Helpline on 08000 121700, local police on 101, or 999 in an emergency.”

Cambridgeshire officers were supported by the Terrence Higgins Trust, the NHS and Rape Crisis.

* A 44-year-old man was arrested on suspicion of controlling prostitution for gain and immigration matters at an address in Park Road, Peterborough. A 37-year-old woman was also arrested for immigration offences. Both were released under investigation.

* Premises in Arbury Road and Cherry Hinton Road in Cambridge were visited, advice was given and a 33–year-old woman was arrested for immigration offences.

*A premises in Dogsthorpe Road, Peterborough, was visited where a 34-year-old man was arrested on suspicion of controlling prostitution for gain and released under investigation.

* Six women were safeguarded at the Cambridge premises and three at the Peterborough premises.