The explosion occurred around 10:40 a.m. at Timberline Services on Swedesboro Road in Harrison Township, Harrison Township police said.
Leni Fortson, regional director of OSHA, confirmed that her federal agency had sent an inspector to investigate the report of a death.
The truck may have been parked in a building when it exploded, according to one report.
The investigation remains ongoing in conjunction with the Gloucester County Prosecutor's Office and Fire Marshall, police said. Motorists are urged to avoid the area.
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