A North Carolina man has died and three firefighters were injured when a commercial-grade fireworks depot caught fire and exploded.

Emergency services were called to La Grange, Lenoir County, at 3.15pm on Friday to reports that a controlled burn in a hay field was spreading towards a building containing fireworks.

Upon arrival they found the property owner Randy Herring, 56, trying to prevent the fire from reaching the structure.

Moments later the cache of fireworks exploded fatally wounding Mr Herring and injuring three firefighters from the La Grange Volunteer Fire Department.

The injured firefighters were taken to ECU Health Medical Center in Greenville for treatment. Two have since been released from hospital, and one was transferred to the North Carolina Jaycee Burn Center in Chapel Hill for further treatment.

Firefighters worked throughout the night to dampen down hotspots, with unexploded fireworks being scattered in the surrounding fields.

Witness Micah Monroe told WRAL the explosion was “massive”.

“There was this extreme explosion that shot well over, I’d say six to seven hundred feet in the air,” Mr Monroe said.

“It was a tremendous bang and followed with little after shocks… that we now know were fireworks.”

Friends took to social media to pay tribute to Mr Herring, a pastor at Berean Fellowship Church in LaGrange.

La Grange Fire Department chief Ryan Riley wrote on Facebook that Mr Herring was a firefighter “and a person we could call on anytime for a helping hand”.

The Lenoir County Fire Marshal’s Office is coordinating an investigation into the explosion with officials from the North Carolina State Bureau of Investigation, the North Carolina Office of the State Fire Marshal, the NC Forest Service, and the Bureau of Alcohol, Tobacco, Firearms and Explosives.