Wyoming County coroner Thomas Kukuchka said the pilot contacted a nearby tower around 10:30 p.m. Saturday saying he would attempt to return to another airfield nearby.
"That's when he went off radar," Kukuchka said Sunday.
The names and ages of those on board have not been released, but Kukuchka said three men, a woman and a child were on board.
"It appears to be a father and son, a father and daughter and the pilot," he said.
He said his office was trying to reach family members of the deceased in Leesburg, Va., Ellicot City, Md. and Kintnersville, Pa.
The Federal Aviation Administration said the helicopter took off from Greater Binghamton Airport in New York but officials there said it had actually originated at a smaller airfield nearby, Tri Cities Airport in Endicott. A phone message left at Tri Cities Airport was not immediately returned Sunday night.
The helicopter was bound for Jake Arner Memorial Airport in Lehighton, the FAA said.
State police and FAA personnel were still on the scene Sunday evening, according to Trooper Adam Reed, a state police spokesman. He said additional details would be released as the investigation progresses.
Kukuchka said there were severe thunderstorms in the area Saturday night, although it was not clear if weather played a role in the crash. The coroner and police said rough weather contributed to the difficulty of the search; the wreckage was located shortly before 2 p.m. Sunday.
The National Transportation Safety Board will lead the investigation, the FAA said.