Authorities have dismantled the biggest modern slavery ring ever discovered in the UK. The network forced more than 400 people to work for almost nothing, while the criminals behind it earned a fortune.

Eight members of the  well-organized Polish human trafficking gang are thought to have made more than £2 million ($2.5 million) before they were jailed last week. Some had been sentenced as early as February, but reporting restrictions on the case prevented them from being named until last week. 

The ringleaders tricked vulnerable individuals from Poland, many of whom are homeless, alcoholics or ex-prisoners, to work in the UK. They promised the victims they would have  jobs and accommodation, but they were instead forced to live in cramped and rat-infested houses, some without heating or working toilets. 

"Most felt powerless to escape, with no knowledge of the area, little or no English language skills, and no-one to turn to for help," Detective Chief Inspector Nick Dale of West Midlands Police said. "Their lives were reduced to misery and they all have the physical and psychological scars of their exploitation."

Some of the victims claimed they were forced to wash in canal water, and were fed expired food. They were also forced to work at waste recycling centers and farms in the West Midlands, for as little as 50p (63 cents) per hour. The traffickers also took most of their salaries and refused to provide them medical care. 

Those who complained were humiliated, threatened and even beaten up. So-called “house spies”, trafficked individuals who later became trusted informers, kept an eye on these trafficking victims. 

The gang’s illegal operation was eventually unravelled, after two of the victims escaped their captors and sought help from Hope for Justice.  The charity then reported the organization to the West Midlands Police, who launched an investigation in February 2015. 

Dale said at least eight people exploited the victims. Police identified a total of 92 victims but believe there are are least 350 more who could be too scared to give evidence, had already left the country, or could not be traced. 

"This was trafficking and exploitation on a massive scale; this gang treated these people, their fellow countrymen, as commodities purely for their own greed," Dale said.

Gang members Juliana Chodakiewicz, Natalia Zmuda, Marek Chowanic, Marek Brzezinski, Justyna Parczewska,  Ignacy Brzezinski, West Bromwich, Wojciech Nowakowski, and Jan Sadowski were convicted for their involvement in the slavery ring. Their sentences range from three to 11 years.