Around 40 firefighters are tackling a large gorse fire at a nature reserve in Belfast Harbour Estate.
The Northern Ireland Fire and Rescue Service were tasked to the scene at around 3.44pm on Sunday.
Large plumes of dark smoke from the blaze could be seen for miles, with much of it drifting onto the M2 motorway.
Nine fire appliances and a high volume pump are being used to tackle the blaze, while a command support unit is also in attendance.
A drone is also being used to evaluate the extent of the fire.
A Northern Ireland Fire & Rescue Service (NIFRS) Spokesperson said: "This fire is generating high volumes of smoke across North Belfast and the City Centre, the public are advised to close doors and windows to prevent smoke entering residential property.
"NIFRS are being assisted by representatives from other support services, Belfast City Council and Skywatch, to manage this incident. It is anticipated that NIFRS will be committed for several hours into the night.
"Since Friday morning the Regional Control Centre has received 729 calls resulting in a response to 396 incidents across Northern Ireland, 134 of these have involved grass and wildfire. This has been an exceptionally busy Spring period for fire crews who have worked hard in tough conditions to extinguish these wildfires.
"Due to the recent hot weather, grass and gorse is extremely dry and NIFRS would appeal to members of the public not to light small fires or disposable barbecues as these can lead to significant wildfire incidents and damage to the countryside."