Robert R. Trojanowski, 54, was taken by ambulance to Chilton Hospital in Pequannock, as were two Ringwood police officers who jumped in to save him.
Trojanowski fell through the icy lake about 100 feet from shore in the Long Pond Ironworks State Park sometime around 2 p.m., responders said.
Two Ringwood police officers went after him before all three were pulled out by colleagues from Ringwood and West Milford, they said.
The incident two days after two teenage boys -- David Tillberg, 15, of Carteret and 13-year-old Yusef Khela of East Brunswick -- died in separate falls through thin ice.
The deaths brought a plea from Gov. Phil Murphy: “Please stay off and away from frozen lakes and ponds," he tweeted. "No ice is safe ice.”
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