Three people were killed -- James V. LaGuardia, 64, David Fleetwood, 62, and Gerard J. Kozic, 53.
Several others were wounded. Newell was one of three people taken to a hospital after the shooting and later released into police custody, Geoffrey Roche, spokesman for the Pocono Medical Center, told CNN Tuesday.
Newell was arraigned Tuesday morning on charges of criminal homicide, Pennsylvania State Police Sgt. Brian Vadell said. Newell was in Monroe County jail during the video arraignment, Vadell said. No plea was entered.
The shooting suspect was limping, shirtless and handcuffed as authorities escorted him into state police barracks Monday night. When a reporter from CNN affiliate WFMZ asked whether he had anything to say about what had happened, it didn't take him long to answer.
"They tormented me for 23 years," Newell said. "I couldn't take it."
Court documents reveal dramatic details
The terror began Monday night even before the gunman entered the building, police said.
Ross Township's monthly supervisors meeting had just started when the shooter marched toward the municipal building in Saylorsburg with a long gun and fired through the windows.
Court documents obtained by CNN paint a dramatic picture of the shooting and its aftermath.
The shooter used a semi-automatic rifle to open fire on the meeting, according to a probable cause affidavit filed by police.
When police arrived in the meeting room, one victim lay dead on the floor. Newell was also pinned to the ground on his stomach, with a gunshot wound in his leg, the affidavit says.
As authorities took Newell to the hospital, Pennsylvania State Police Trooper Nicolas de Iglesia said he heard Newell say, "I wish I killed more of them."
At the hospital, the affidavit says, Newell told police he'd planned to kill the township's solicitor and supervisors, and thought he would get killed while doing it.
Inside the gunman's vehicle, police said, investigators found 90 rounds of ammunition.
Witness: 'It was a nightmare'
Pocono Record reporter Chris Reber watched as plaster flew off the walls, he said in a first-hand account that appeared in the newspaper. He was covering his first board meeting.
He heard more than 10 shots.
"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," according to the newspaper account.
Another witness, Cleoria Campodonico, sobbed as she told CNN that the shooting was "the worst thing I have seen in my whole life."
"I am scared for the rest of my life for those images," she said, vowing to never go back in the building again.
She said that she, too, called 911 when the shooting happened and then phoned her husband to tell him that she loved him. She thought she would never see him again, she said. She then called her daughter to tell her the same thing.
A man protected her, she told CNN, and he was shot in the stomach twice. She does not know if he survived.
"I owe that man my life for protecting me," she said. "Oh my God, it was a nightmare."
Complaints about Newell
The Pocono Record newspaper reported in a story on June 10 that Newell, after an 18-year battle, had been ordered last year to vacate his property, which was called an eyesore by the board of supervisors, the elected body that sets policies and laws for the community of 5,400.