Children as young as 14 were working night shifts at beleaguered haulage firm Reid's Transport, an assembly member has claimed in Stormont.
Workers should receive wages owed by Christmas
North Antrim MLA Daithi McKay of Sinn Fein said sacked workers on the picket line told him some employees had been working more than 70 hours a week.
Employment Minister Sir Reg Empey said he had already referred the most serious allegations to the police.
Meanwhile, administrators say owed wages will be paid before Christmas.
Sir Reg has been meeting administrators of the Cloughmills-based firm, which collapsed last week with the loss of 200 jobs.
He said back-pay would be available to those entitled to it, at a rate of just over £300 a week.
The Cloughmills firm went into administration on Wednesday
The workers had lifted their blockade at the company's gates on Friday afternoon, but it resumed because of confusion about when or if the money would be paid.
Some workers at a meeting on Monday night said they were not confident the money would be paid.
Garth Calow of administrator PricewaterhouseCoopers has called for the blockade to end so that lorries can return to the yard at Cloughmills.
Some trucks have been abandoned at the roadside in England and not all have been accounted for.
"Allowing vehicles to enter and leave the site will let me complete deliveries and will safeguard company assets on behalf of the creditors, who include the ex-employees and sub-contractors," he said.
Mr Calow said his company had begun an investigation into the reasons why Reid Transport collapsed.
Directors of the company, Liam and Shaun Reid, have not been seen by the workers or the administrators.