LAWRENCEVILLE, Ga. -- A fire heavily damaged a Lawrenceville business Wednesday morning and sent a plume of dark smoke over parts of Gwinnett County.

The three-alarm fire was discovered just after 7 a.m. by passing motorists who saw smoke coming from a building at East Crogan Street and Scenic Highway in Lawrenceville. One of the callers was an off-duty firefighter.

A sign outside the warehouse-type building identified the business as "Artistic Building Supply."

When firefighters arrived, they entered the building and conducted a search. However, they were forced to back out by intense fire and heat conditions.

News Chopper 2 was over the scene and video showed flames through the roof of the building.

In addition to intense flames, firefighters also had another hazard. Water from the fire hoses began to freeze on the roadway and sidewalks, making it difficult for crews to walk without slipping. A sand truck was called to assist.

The exact cause of the fire is still under investigation. Gwinnett Fire Investigators said the ATF is also assisting to determine what caused the fire, which is common practice on major fires involving large commercial structures.