Two brothers who recruited staff for UK recruitment firm Transline, which supplied Sports Direct, have been convicted and jailed for six years each under the Modern Slavery Act.

The two brothers, Erwin and Krystian Markowski from Poland, recruited 18 vulnerable men from Poland to work at Sports Direct’s Shirebrook warehouse. The brothers kept most of their earnings and controlled their bank accounts.

The brothers employed a “spotter” in Poland to identify vulnerable people who could be sent to the UK on the promise of work. The brothers would then open bank accounts and control them while keeping most of the workers’ earnings. The workers, who also had their passports taken from them, were left with £90 from weekly pay that should have been £265. The brothers were caught after one of the victims reported his experience to the police.

A spokesperson for Sports Direct said in a statement: “We welcome the conviction of these two individuals, who were brought to justice after being reported to police by the Transline agency and Sports Direct in February 2016. It sends a clear message that we will not tolerate these kinds of behaviour.”

A spokesman for Transline also commented, “These two brothers have no association to Transline,” Transline added that it had reported complaints of exploitation related to the case to the police.

“We have stringent and thorough checks in place on identities and bank and payment details to prevent this type of criminal activity, and find any instances deplorable and cruel,” Transline said.

In 2015, an undercover investigation by the Guardian found that Sports Direct had been paying their employees below minimum wage.

Last year, the Recruitment and Employment Confederation (REC) investigated Transline after a parliamentary inquiry suggested that their employment practices possibly breached the REC code of ethics due to its employment practices. The REC closed the investigation and stated that no further action would be taken.

UK trade union Unite has called for further investigation into Transline.