The fire consumed 25 to 30 acres of land and took about three hours to bring under control, the National Park Fire Department said.
National Park and Westville fire departments were dispatched shortly before 4 p.m. on Sunday, Feb. 5.
Additional brush units were called from West Deptford and Deptford fire departments.
The land off Grove Avenue is owned by the U.S. Corps of Engineers.
Investigators have a "person of interest" as the possible arsonist, but the suspect's name was not released, NJ Advance Media reports.
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