Emergency personnel are continuing operations at the fire scene on Queen's Island within Belfast Harbour.
The incident involves a significant amount of scrap metal and marks the second major conflagration of this nature at the harbour this year.
Smoke can be seen drifting across Belfast Lough, with visibility from Belfast City Airport affected by the ongoing smoke.
Firefighters are working in coordination with Belfast Harbour fire tugs to suppress the flames.
An air unit has also been deployed to assist in bringing the blaze under control.
Crews remain on site through the night to monitor the situation and prevent any potential reignitions.
The operation is currently ongoing as authorities assess the full extent of the damage.
Declan McPhillips captured images showing firefighters at the scene of the incident on Thursday morning.