Human traffickers in the UK are increasingly using drugs and alcohol as a means of controlling and forcing vulnerable British men and women into slave labour and sexual exploitation across the country, according to the Salvation Army.

Figures from the charity show that this year they have seen a doubling of the number of British people coming into their statutory support services after being identified as victims of slavery by the government.

Many were homeless and had existing drug and alcohol addictions that had made them a target for traffickers, who then used their addiction to coerce them into forced labour, prostitution or criminal exploitation such as selling drugs or forced begging.

Kathy Betteridge, director of anti-trafficking and modern slavery for the Salvation Army, said that although the figures were still low compared with victims of trafficking from other nationalities – 86 British people were referred to their services between June 2017 and July 2018 – it was an increasing and disturbing trend.

“The figures clearly show that forced labour among [Britons] and victims from other nationalities has increased,” she says.

“We are discovering that men in particular with misuse of drugs or alcohol issues are increasingly vulnerable to becoming victims of modern slavery, specifically targeted by exploiters who encourage them to work in return for small amounts of money or substances and often ending up in debt bondage and sometimes being held in captivity.”

The Salvation Army has identified ways that traffickers are targeting potential victims. This includes “cuckooing”, where drug dealers befriend vulnerable addicts and supply them with narcotics before moving into their homes. They then threaten to withdraw supply of drugs or use threats and intimidation to get their victims to sell the substances.

Adults are also being used as county lines drug mules, transporting drugs from urban into rural areas. Drugs and alcohol are also being used to force vulnerable women into prostitution in the growing numbers of pop-up brothels operating across the country.

Homeless people are also increasingly becoming victims of modern slavery, lured by traffickers with promises of work, housing and narcotics. They are then used as forced labour, to sell drugs or in other forms of criminal exploitation.

One client was a British man who had battled substance abuse problems for many years. He became homeless and on the streets was targeted by criminals who forced him to sell drugs on their behalf across the country with promises of money, which turned into threats and intimidation. Arrested by police, he was recognised as a potential victim of modern slavery and referred to the charity for support. He is now drug-free and living in supported accommodation.

The Salvation Army says that it provides victims with tailored support and access to specialist treatment and accommodation services. Yet others in the anti-slavery sector warn that existing statutory support is not set up for people with complex issues and addictions. Some adults entering safe housing end up having to leave because of their dependency.

Robin Brierley, chair of the West Midlands Anti-Slavery Network, said that they are seeing increasing numbers of people who have been identified as victims of slavery ending up destitute, homeless and re-trafficked shortly after exiting safe houses.

“If people go into these services with drink or drug addiction or other mental health issues, then sometimes they are unable to cope and often end up back on the streets and being exploited again,” he said.

The London charity Hestia helped 218 male slavery victims this year who had been forced to work in farms, construction sites and cannabis factories. It found many of those victims had slept rough after escaping their traffickers and 92% had mental health issues.

In total, 1,856 victims of slavery from 86 different countries were referred to the Salvation Army between July 2017 and June 2018. The majority – 45% – had experienced forced labour, while 42% had been sexually exploited and 14% trapped in domestic servitude. The biggest group were Albanian women, who had been sex trafficked by criminal gangs.