WINTHROP — Andrew Balcer was known as a quiet kid who threw shot put, loved microscopes and interacted with friends on the messaging app Snapchat.

He was close with his mother, known to friends as Ali, going on runs with her and joining her, an assistant veterinarian, as she worked with animals. A photo posted in September on her Facebook page shows them standing side by side after a run, arms wrapped around each other – she’s looking up at her son with a bright, beaming smile as he looks straight ahead at the camera.

To his peers, Andrew could be pleasant and respectful. At Winthrop High School, he was a senior with a reputation for good grades and behavior, recalled as an “academically superior student” by the school superintendent.

But he could also be distant, even rude. This past summer, some of his classmates at Winthrop High didn’t know what to think when Andrew sent out a series of Facebook messages apologizing for anything he had done to offend them and vowing to be a better person.

And when news spread Monday that the 17-year-old had been arrested and charged with murdering his parents – Antonio “Tony” Balcer and Alice “Ali” Balcer, both 47 – many in the Winthrop area were stunned.

“It’s shocking,” Mary Sheridan, a doctor at Winthrop Veterinary Hospital who knew the boy and worked with his mother, said in an interview Tuesday morning. “It doesn’t make any sense. They were a close family.”

Sheridan made the comments shortly before entering the Balcers’ property on Pine Knoll Road to retrieve a dog that belonged to the family.

Andrew Balcer made his first court appearance Tuesday at the Capital Judicial Center in Augusta, where a judge ordered the teenager to undergo a psychological evaluation. The prosecution has requested a hearing that would allow Balcer, who turns 18 next month, to be tried as an adult on two counts of knowing or intentional murder.

A probable cause affidavit that would detail the police account of the allegations – including how Antonio or Alice Balcer were killed – has been sealed.

Police would not say how the couple died because of the ongoing investigation. Their bodies were brought to the state Medical Examiner’s Office and were undergoing autopsies Tuesday.

The Balcers lived at 10 Pine Knoll Road in a white, ranch-style home where a Christmas wreath hung above the garage.

Police were called there shortly before 2 a.m. Monday and found the parents dead in the home. Andrew Balcer has an older brother in his 20s, and both were at home when police arrived.

After characterizing the deaths as “highly suspicious” in the morning, police said in the afternoon that they had charged a teenage boy with two counts of murder.

SCHOOL, NEIGHBORHOOD IN SHOCK

Neighbors, family members, friends and co-workers of the deceased were reeling from the news Tuesday morning.

At Winthrop High, extra counseling services were available to any students or staff affected by the tragedy.

“I was very surprised,” Corinna Coulton, a senior whose locker was near Balcer’s, said of the news that he had been charged with murder. “He’s very smart, very sweet and polite.”

Speaking after school, Coulton said she visited one of the counselors Tuesday because she was interested in organizing a schoolwide meeting to help dispel the rumors that have been circulating since police first began investigating the killings.

“I think a lot of people have a lot of questions,” Coulton said. “Some people seem very scared and concerned. People didn’t expect this from Andrew.”

“It makes you on edge,” said Sarah Spahr, another senior who had physics class with Balcer and was with Coulton after school Tuesday.

Such concerns have not been limited to the student population, said Gary Rosenthal, superintendent of the Winthrop School District. The district and its staff have weathered multiple tragedies over the years, including the sudden death of one student, Kelsey Stoneton, from a blood clot in 2014, and a series of suicides by football players in the early 2000s.

“Our staff is very stressed because of this,” Rosenthal said. “We have a very humane group of teachers and staff at our schools. When something like this happens, a lot of them really take it personally because they’ve been in the district a long time, they always think about what they could have done to have more of an impact to keep those kinds of things from happening.”

AN ‘EERIE’ MESSAGE

Rosenthal also said that Balcer was, by many accounts, a good student. He was listed on the school honor roll more than once, according to Kennebec Journal archives.

“From what best I know, he was a very good kid, a very good student, an academically superior student,” Rosenthal said. “There were no telltale signs that I know of that would indicate there were any problems, and the family seemed to be well-liked, and the mother was very personable. It’s one of those dilemmas you shake your head at.”

A number of Balcer’s classmates echoed their shock that he could have been charged with such a serious crime, particularly one that involved Alice Balcer.

Brianna McClure, a fellow senior, said she thought he was close with his mother and mentioned that he spent time helping her work with animals.

McClure did not know how Balcer got along with his father.

McClure, like Coulton, also said that Balcer sent a series of Facebook messages to his classmates last summer in which he apologized for past offenses – an act she described as “eerie.”

“He said, ‘Hey, we never got off to a good start, but I’m changing my life this year,'” McClure said. “He used to swear at people and call them names in different languages, but he apologized for all that and said he’s changing his life. Then this happened and we were all pretty confused.”

In downtown Winthrop on Tuesday afternoon, few local business owners said they knew the Balcer family well, if at all. But just about everyone said they were horrified by the killings and offered their condolences to the victims’ loved ones.

“I think it’s awful,” said Tricia Brennan, who works at Bloom Salon on Main Street. “I think it’s shocking.”

Brennan said she knew Antonio Balcer – a retired member of the Coast Guard who belonged to the Exiles Motorcycle Club – through mutual friends and couldn’t fathom how things could have erupted in violence in his family.

“(Antonio) was a great, great guy,” she said.

SCARED WOMAN AT NEIGHBOR’S DOOR

Melissa Shannon, who lives a few houses away from the Balcers on Pine Knoll Road but didn’t know the family, was surprised that such a crime could have happened on her road. Shannon, 36, lived there as a child and recently moved back to look after her father, who was diagnosed with lung cancer.

Shortly before 2 a.m. Monday, Shannon called police to Pine Knoll Road after a woman she did not recognize knocked on her door and said a man was trying to hurt her. The woman seemed to have come from the direction of the Balcer household, Shannon said, and continued onto another house after speaking to them.

Maine State Police spokesman Steve McCausland declined to comment Tuesday on Shannon’s account, saying he had “no information” about that.

“I know a little more about what has happened now, and I just don’t understand it,” Shannon said. “That person who was here must have been so scared.”