Two victims were flown to Lehigh Valley hospitals, where one died, according to state police.
Pennsylvania State Police named the gunman in the shooting at a Monroe County municipal meeting that left three people dead tonight.
Rockne Newell, 59, of Ross Township, approached the township municipal building shortly before 7:30 p.m. with a long gun and began firing though windows before entering the building, state police in Lehighton said at a news conference about four hours later.
Police said the gunman had an ongoing dispute with township officials over the possible condemnation of his property. They said 15 to 18 residents and township officials were at the meeting.
The shooter was treated at a hospital and released to police custody, authorities said.
A Pocono Record reporter, Chris Reber, said in a first-person account of the shooting that West End Open Space Commission Executive Director Bernie Kozen "bearhugged him and took him down. He shot (the shooter) with his own gun."
"They're certainly courageous in what they did," state police Lt. Robert Bartel said of the people who sprang to action, adding more casualties would have been likely had they not acted.
Two victims were dead when police arrived. Two more were flown to Lehigh Valley hospitals -- one died at a St. Luke's Bethlehem campus, another is being treated at Lehigh Valley Hospital in Salisbury Township, police said.
A fifth person suffered a graze wound, police said.
The identities of the victims was not released, pending notification of their families. Autopsies are scheduled for Wednesday, officials said.