BRUNSWICK, Ga. – Investigators are working to determine what started a fire that destroyed two Brunswick warehouses.

That fire broke out Saturday at the Marine Port Terminal Facility on Newcastle Street, which is part of Georgia Ports Authority.

No one was hurt in the fire, but it spread dangerously close to nearby homes. The smoke was so dark it was difficult for neighbors to see down the street and across the water. The flames were visible for miles.

It was determined that two warehouses were destroyed. Crews prevented a third building from becoming burned.

"We got a 911 call for the warehouse on fire. Units responded," Fire Marshal Rhett Fairfield said. "When we showed up, we immediately requested assistance units based on the size of the fire."

WATCH: Viewer video of Brunswick Warehouse fire

It took crews from at least seven local departments to put out the flames. The fire was contained by nightfall.

Officials told News4Jax that although the Georgia Ports Authority owns the building, it is leased to and operated by Canadian-based company Logistec. News4Jax is told that inside the warehouses were wood pellets, a product of the company.

"Logistec was both loading a ship with this product and also unloading from trucks and rail into the warehouse," said Curtis Foltz, executive director of the Georgia Ports Authority.

Through a search on the Occupational Safety and Health Administration website, News4Jax found Logistec has received violations.

During a planned inspection in 2011, OSHA listed 18 violations at the Brunswick warehouse. Among them, one violation that read "employees were exposed to the hazards of being burned from a fire and or not being able to exit the building due to non-functioning sprinkler system."

A follow-up inspection a year later showed only one violation.

No injuries were reported and everyone is accounted for.

"I can replace facilities, we can rebuild all of these sites, it really is all about the people, and we're really blessed that no one was injured in this," Foltz said.

News4Jax contacted an employee with the safety department at Logistec, who said he could not answer questions or give a statement.

Fire crews do not have a cause of the fire or an estimate of damages.