The man suspected of killing more than two dozen people at a school in the U.S. state of Connecticut was an honors student who lived in a prosperous neighborhood with his mother.

Adam Lanza killed his mother at their home before driving her car to Sandy Hook Elementary School and armed with at least two handguns carried out the massacre before taking his own life, officials said. A third weapon, a .223—caliber rifle, was found in the car, and more guns were found inside the school.

The 20-year-old may have suffered from a personality disorder, law enforcement officials said.

Investigators were trying to learn as much as possible about Lanza but so far, authorities have not spoken publicly of any possible motive. Witnesses said the shooter didn’t utter a word.

Lanza’s aunt said her nephew was raised by kind, nurturing parents who would not have hesitated to seek mental help for him if he needed it.

Marsha Lanza, who lives in the state of Illinois, said she was close with Adam Lanza’s mother and sent her a Facebook message Friday morning asking how she was doing. Nancy Lanza never responded.

Marsha Lanza described Nancy Lanza as a good mother and kind-hearted.

If her son had needed counselling, “Nancy wasn’t one to deny reality,” she told The Associated Press late Friday.

Marsha Lanza said her husband saw Adam as recently as June and recalled nothing out of the ordinary about him.

Catherine Urso, who was attending a vigil Friday evening in Newtown, Connecticut, said her college—age son knew the killer and remembered him for his alternative style.

“He just said he was very thin, very remote and was one of the goths,” she said.

Lanza and his mother, Nancy, lived in a well-to-do part of Newtown, a prosperous community of 27,000 people.

A grandmother of the suspect who is also the mother of Nancy Lanza was too distraught to speak when reached by phone at her home in Florida.

“I just don’t know, and I can’t make a comment right now,” Dorothy Hanson, 78, said in a shaky voice as she started to cry. She said she hadn’t heard anything official about her daughter and grandsons. She declined to comment further and hung up.

A law enforcement official speaking on condition of anonymity said investigators believe Lanza attended the school several years ago but appeared to have no recent connection to the place.

At least one parent said Lanza’s mother was a substitute teacher there. But her name did not appear on a staff list. And the law enforcement official said investigators were unable to establish any connection so far between her and the school.

Adam Lanza’s older brother, 24-year-old Ryan Lanza, was being questioned, a law enforcement official said. He told authorities that his brother was believed to suffer from a personality disorder, the official said, speaking on condition of anonymity because he was not authorized to speak on the record about the unfolding investigation.

The official did not elaborate, and it was unclear exactly what type of disorder he might have had.

Ryan Lanza had been extremely cooperative and was not under arrest or in custody, but investigators were still searching his computers and phone records. Ryan Lanza told law enforcement he had not been in touch with his brother since about 2010.

Brett Wilshe, a friend of Ryan Lanza’s, said he sent him a Facebook message Friday asking what was going on and if he was OK. According to Wilshe, Lanza’s reply was something along the lines of- “It was my brother. I think my mother is dead. Oh my God.”

Adam Lanza attended Newtown High School, and several local news clippings from recent years mention his name among the school’s honor roll students.

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