State police in Lehighton confirmed the three deaths and said the gunman, identified as 59-year-old Rockne Newell, had an ongoing dispute with township officials over the possible condemnation of his unkempt property. They said about 15 to 18 residents and town officials were at the meeting place, a short drive from Newell's property, when the gunfire erupted.
The shooting, which injured at least two other people, happened shortly before 7:30 p.m. during Ross Township's monthly meeting, Monroe County emergency management director Guy Miller said. The gunman, who appeared to be "shooting randomly," was captured and was treated at a hospital, he said.
Two people died at the scene, and a third person died after being flown to a hospital. Police confirmed that at least one of the dead was a township official but declined to give additional details. A fourth person, a woman, was in surgery with undisclosed injuries.
Investigators said Newell began shooting as he approached the building and continued as he walked into and through it. He then went back out to his vehicle in the parking lot, retrieved a handgun and went back into the building, firing more shots, police said.
Pocono Record reporter Chris Reber said he was at the township building when a man armed with a long gun with a scope shot through a wall into the meeting place, in a rural area of northeastern Pennsylvania about 85 miles north of Philadelphia.
"The thing that got my attention: plaster flying out, blowing out through the walls. Witnesses would later tell me they saw pictures exploding away from the walls," Reber said in a first-person account told to his editors Marta Gouger and Chris Mele. "I heard more than 10 shots."
He said he crawled out to a hallway, exited the building and took cover behind a vehicle.
"The gunman was this guy wearing a blue Hawaiian shirt," he said. "I saw him go back out to his car, a silver Impala, and get another gun.
"It wasn't real to me until I went back inside and saw people bleeding."
A local official at the meeting grabbed the shooter and subdued him, Reber said.
"(West End Open Space Commission executive director) Bernie Kozen bear-hugged the gunman and took him down," Reber said. "He shot the shooter with his own gun."
State police said they believed two people may have subdued the gunman, who was shot in one of his legs.
U.S. Rep. Matt Cartwright, who represents the state's 17th District, said he was "appalled at the atrocities that claimed the lives of innocent citizens in Ross Township." He said he had heard about what Kozen did to prevent more bloodshed.
"Mr. Kozen is a true hero tonight," Cartwright said in an emailed statement.
Kozen's wife, reached by telephone at their home Monday night, said he wasn't there and she was unsure when he'd be back.
Newell had been in a long-running dispute with township officials over the dilapidated condition of his property, state police Capt. Edward Hoke said. The township supervisors voted in February 2012 to take legal action against Newell for violating zoning and sewer regulations, according to meeting minutes posted online.
The ramshackle property includes an old camper in the front yard filled with wooden pallets, pieces of what appear to be old railroad ties and trash. A garage leans and appears close to collapse, and a propane tank sits inside an old dog house.
State police, who guarded the property early Tuesday, were awaiting a search warrant so they could enter it.
In June, the Pocono Record wrote a story about what it said was an 18-year fight between the township and Newell over his property.
Monroe County Court in August 2012 sided with the township and ordered Newell to vacate and never again occupy or use the property unless he had the permits to do so. The report said Newell had been living out of a car and in abandoned buildings since being ordered to vacate.
Newell told the newspaper he was unemployed for years after an injury from a crash and had nowhere else to go.
"They have no right to kick me off my property," he told the newspaper. "They call my property an eyesore. When I bought it, it was one of only three properties on the entire road that didn't have what they call junk."
Newell was in police custody after being treated at the hospital Monday night and couldn't be reached for comment, and there was no telephone number listed for his property.
Ross Township has about 5,500 residents. According to its website, the board of supervisors meets at 7 p.m. on the first Monday of each month.
Associated Press writer Michael Rubinkam and photographer Chris Post contributed to this report.