The captain of the Celtic Star ship has admitted that the company owes its staff €25,000 in arrears.
It follows a stand-off on board the vessel today as nine Romanian crew members are refusing to leave the ship and allow it to sail because they say they are overworked and underpaid.
Officers from the International Transport Federation boarded the freighter early this morning.
They say their inspections found that some of the men have broken ribs from an accident which occurred last week, while the full hours being worked by the men are not being recorded.
It's expected that the Port State Control will inspect the ship tomorrow.