About 16 hours after crews from at least three counties began tackling a massive blaze at Nicos Polymers Group in Plainfield Township, firefighters were still battling smoke and hot spots.

Much of the building's steel structure at 730 Bangor Road (Route 191) collapsed because of the fire's searing heat, and what was left standing was being torn down by excavators.

Belfast Road, Clyde Street and the intersection of Route 191 and Sullivan Trail remained closed as of 9 p.m. Crews will monitor hot spots throughout the night.

Anyone with respiratory problems is urged to stay indoors until the smoke clears completely.

There have been no reports of injuries.