Democratic Unionist Party (DUP) MLA Stephen Dunne described the fire as “quite a major incident”.
“It has caused considerable concern within the local community,” he told the BBC’s Evening Extra programme.
“At this time in the evening traffic is always quite considerable and the heavy, thick smoke has added to that traffic congestion.”
Dunne said the fire was in a “very central location”.
“It’s mainly made up of factories and car dealerships and the local recycling centre is there and quite a number of businesses.”
He said “a number of employees” were based in the area and there was “quite a lot of residential housing in close proximity to the fire”.
North Down MP Alex Easton urged people to stay away from the area to allow the emergency services to carry out their work and keep access routes clear.
“I want to pay tribute to the firefighters and all emergency personnel responding in difficult circumstances,” he said.
“I hope and pray that no one has been hurt.
Alliance Party MLA Connie Egan praised the NIFRS for its “prompt and professional response” to the fire, which she said could have caused “even more damage had they not managed to bring it under control quickly”.
“This was a very major fire and has obviously caused quite a lot of concern to those living nearby.
“My thoughts are with the team at Fusco, who will be incredibly distressed. I just hope that no one has been injured as a result.”