Byram Police, Fire and Lakeland Emergency Squad responded to Tomahawk Lake in Sparta around 6 p.m. on reports of a swimmer that went underwater and had not resurfaced, the Byram Township fire department said on Facebook.
The crews were met at the scene by Tomahawk Lake lifeguards, who had already begun the search, authorities said.
A short time later, the Morris County Dive Initiative was requested for assistance due to “uncertainty and conflicting stories,” authorities said. The initiative brought search units from Parsippany, Boonton, Pequannock, Lincoln Park and Pompton Plains, as well as boats equipped with sonar from fire departments in Mahwah and Wyckoff.
Meanwhile, state police conducted a helicopter search of the area.
After scouting the area for several hours with numerous dive and grid searches, the initiative was called off, and no victims were located.
The Sussex County Fire Marshals office and Sussex County OEM also assisted at the scene.
The incident remains under investigation, the Byram Township Fire Department said.
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