A group of 20 workers with freight company Target Express started a sit-in at a Little Island depot earlier today.
Almost 400 jobs are at risk at the company across Ireland and Britain, which has announced it is to cease trading.
In a statement today, the workers said they would not leave until they had received outstanding pay, either an assurance about their jobs or an a redundancy payment.
They also said they would block all merchandise moving in and out of the depot.
Representatives from the Communications Workers’ Union are due to visit the Little Island premises tomorrow.
Managing director Seamus McBrien blamed the Revenue Commissioners for the closure.
He said the company had paid €1 million to the Revenue Commissioners in the last six weeks, but the Revenue still rejected a deal which would have seen the company pay off a further €175,000 from an overall outstanding liability of €300,000.