Joel Shannon, Chris Woodyard, Julie Makinen and Amy DiPierro | USA TODAY

Nick Oza (ozan), Arizona Republic

SAN DIEGO – Before Saturday, John T. Earnest was known only as a quiet, successful student and an accomplished pianist.

On Sunday, his church reeled, calling a special session to address the news: Earnest had been detained in connection with Saturday’s deadly synagogue shooting near San Diego.

His name had also been linked to a racist online posting that praised mass shooters, spoke of a plan to "kill Jews," and extensively cited scripture.

Police had apprehended him along Interstate 15. A rifle was found in the front passenger seat, police said.

Earlier, one woman was killed and three others wounded when a gunman wielding a AR-style assault weapon entered a synagogue during Passover services at the Chabad of Poway temple and opened fire.

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The suspect, a 19-year-old student at Cal State University San Marcos, is a part of a family known as regulars at the Escondido Orthodox Presbyterian Church.

The suspect’s father, John Earnest, is listed as an elder. Pastor Zach Keele said Sunday the younger John always came with his family but was very quiet.

Officials have said they found a "manifesto" posted online around the time of the attack and are working to verify its authenticity.

"I did not want to have to kill Jews," an online text reads in part. It is attributed to a poster by Earnest's name. "But they have given us no other option. I’m just a normal dude who wanted to have a family, help and heal people, and play piano."

It goes on to use repeated slurs and lists Adolf Hitler as an inspiration. It mockingly requests that its author be called a "white supremacist" and "anti-Semite."

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1 dead, 3 wounded in shooting at synagogue near San Diego

On Sunday in Escondido, the suspect's pastor held a session to specifically talk about the shooting and to offer sympathy for the victims. Keele rebuked the manifesto, saying "there is no superior race. We are all created equal." He said also "we are committed to loving all people."

He called the crime “unspeakable in so many ways” and said “we are surprised and we are shocked.”

The attack in Poway, about 25 miles northeast of San Diego, has been called a hate crime by the city's mayor, President Donald Trump and California Gov. Gavin Newsom.

Keele said he took heart that the manifesto said that the suspect's family did not radicalize him.

The suspect was charged Sunday with one count of first-degree murder and three counts of attempted first-degree murder, the San Diego County Sheriff's Department announced in a news release. He had no previous contact with law enforcement.

"We believe he acted alone and without outside support in carrying out the attack," the release reads.

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He is also being investigated in connection with an arson attack on a mosque in nearby Escondido, California, in March. The online posting claims responsibility for that crime.

Classmates and published accolades suggest that the suspect lived a generally shy but accomplished academic life.

Palini Ramnarayan, who was in Earnest’s class at Mt. Carmel High School and now studies at Cornell University, recalled him as “very quiet.”

“I think we all just perceived him as very shy. He played piano at the talent show every year and was absolutely amazing. He kept to himself most of the time and honestly it was hard to know what he was thinking,” she said. “He was very clear about his political ideologies in our AP government class. He's a staunch hard-right conservative who's driven by Christian values.”

Owen Cruise, 20, was a classmate of the suspected shooter and a student of his father, John A. Earnest, a longtime teacher at MCHS.

Cruise said he was in disbelief when he saw the name of the suspected shooter because the suspect was "a friend to everybody, including many Jewish students" at their high school.

“It doesn’t sound like the John that I know, or knew,” he said of a letter posted online that supposedly describes the shooter's hateful motives. “It sounds like someone who’s been brainwashed by associating with the wrong crowds.”

The year he graduated, the suspect was honored for his academic achievements along with about 30 other Mt. Carmel classmates in a program called F.A.C.E., or Fraternity of Academic and Civic Excellence.

In a short bio posted by the program, he was pictured in a dark suit and red tie. He had "an excellent work ethic," the biography said. He was an accomplished pianist and a member of the varsity swim team. He had a GPA of 4.31.

In a 2017 interview ahead of a Mt. Carmel High School talent show, a dark-haired student wearing a grey swim team hoodie blankly identified himself as Earnest.

"Hey, I'm John Earnest," he said, staring into the camera.

His act would be a piano arrangement of Pirates of the Caribbean, he said.

What would he do with the prize money, if he won?

"Save it 'till I need it," he said with a shrug.

He went on to be recognized for his performance in that talent show, as he was for three straight years, his F.A.C.E. profile said.

In the wake of the shooting, the suspect's pastor said he wants to "reach out and express my condolences to the synagogue" and is searching for the best way to do it.

Gerrit Groenewold, an elder at the suspect's church, said he remembers attempting to reach out to the suspect.

"I tried to talk to John several times, but he just never said anything," said Groenewold, who has been attending the church for 15 years. "I think it’s not good if someone is as quiet as that."