(CNN) Ciara Meyer stood directly behind her father as he raised a .223-caliber rifle and pointed it at the chest of a constable who'd come to serve an eviction notice at their apartment.

The constable responded with a single shot.

That bullet went through the arm of 57-year-old Donald Meyer and into his 12-year-old daughter, Ciara, killing her.

Meyer now faces charges of aggravated assault, simple assault, terroristic threats and recklessly endangering another person, according to a Pennsylvania State Police report. He was flown to Hershey Medical Center for treatment after Monday's shooting in Perry County.

The man who shot him, Constable Clarke Steele, is "heartbroken" over the incident, his friend and fellow constable Bill Stoeffler told CNN affiliate WPMT-TV

"He was put in a position from which he couldn't retreat safely," Stoeffler said of the shooting, calling it "every constable's worst nightmare." "He had no other option, really, than what he did."

Comments on a GoFundMe page set up in Ciara's name -- ostensibly to raise money for her funeral expenses and fund a scholarship focused on domestic violence -- reflected the strong emotions her death elicited. A CNN request to verify the page's authenticity was not immediately confirmed.

Some admonished her father for putting his daughter in harm's way. One man said the constable should have stood down and walked away, saying any money owed wasn't worth it. Most paid tribute to the victim in the tragedy.

"Fly high, sweet angel," one woman wrote of Ciara. "Rest in peace."

Police: Father pointed loaded rifle at constable

Donald Meyer knew the constable was coming, Pennsylvania State Trooper Robert Hicks told WPMT. His family had gotten multiple notifications, with the last making it clear a constable was on the way with an eviction notice.

"When they heard the knock, they knew who it was," Hicks said.

When Steele arrived at 10 a.m. Monday, "the suspect opened the door to the residence and then shut it," according to the police report.

Meyer then reopened the door and, after "a brief exchange of words," leveled a rifle that had been concealed and aimed it at Steele.

"Constable Steele, who was in uniform, quickly removed his .40 caliber duty weapon from its holster and fired a single round," the police report said, noting that employees of the apartment complex witnessed the encounter.

That bullet "shattered the bone in (Meyer's) left arm," Hicks told CNN affiliate WHTM-TV , then went into the body of Ciara, who had stayed home sick from school.

She was pronounced dead at the scene, according to the police report.

Investigators recovered the rifle her father had been carrying and found it with "a loaded chamber and a magazine containing 30 rounds."

Girl remembered as 'loving' and 'vibrant'

On its website, the Susquenita School District said that psychologists and counselors would be available to help children make sense of what happened at the Pfautz Apartments.

Superintendent Kent Smith didn't elaborate, saying, "Until permission is received from investigating authorities, the District is not at liberty to share any additional details."

A neighbor who heard the fatal shot told WHTM that she "burst into tears" after learning the girl had died. She dreaded telling her young daughter about it.

"How do you explain that?" said the woman, whom the TV station did not name. "I'm an adult, and I don't understand it."

Online, relatives and friends remembered the "sweet child" whom some called CC.

"Ciara was a loving vibrant 12 year old ," the GoFundMe page said, "(whose) life was cut short far too early."

Constable thrust into difficult position, trooper says

Pennsylvania constables are not police officers but elected officials. They may be tasked with certain aspects of law enforcement in the duty of the courts, according to the Pennsylvania court system.

The Pennsylvania State Police, along with the Perry County district attorney's office, are investigating what happened Monday, but Hicks suggested Steele was unfairly thrust into a difficult spot.

"The father put the constable in a situation where he had to make a decision to use deadly force," the trooper said. "And he did.

"And now we have this tragedy."