HAMMONTON — A forest fire that burned 1,800 acres on Sunday afternoon was declared 100% contained on Monday, helped by showers that fell overnight.

The fire, dubbed the "Jack's Swamp Fire," began near the Burlington-Camden County line southwest of Atsion Lake and forced the closure of a stretch of Route 206 in both directions at Chew Road in Hammonton. The road was reopened around 4:30 a.m. on Monday.

"We had some rainfall overnight. The overnight crews mopped up the hot spots along the edge of the fire control lines and kept it where it needs to be," NJ Forest Fire Control Technician Al Valentino said, adding that the continued rainfall will help keep what's left of the fire "in check."

No structures were threatened by the fire and no evacuations were ordered, according to the Forest Fire Service.

"Jack's Swamp Fire" in Wharton State Forest (NJ Forest Fire Service)

Valentino said the cause of the fire remained under investigation, including the possibility of a lightning strike.

The Forest Fire Service said 40 fire service personnel battled the fire with 10 brush trucks, four water tenders, four tractors and a helicopter.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ

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