Intense flames tore through the Am-Spec Chemical Corporation warehouse in Gloucester City.
The multi-alarm fire was brought under control just after 6:00.
The plant sits just off the Delaware River in a mostly industrial area approximately six blocks south of the Walt Whitman Bridge. The closest residents are about four blocks west of the plant.
Action News was told the bio-chemical company recently moved and officials are not sure what chemicals remain in the building.
Firefighters remained on scene through most of the morning dousing hot spots.
Investigators say it's still too early to determine a cause.
