Two days after a shooter took the lives of two children attending Mass during their first week of school, the Minneapolis community is mourning its deep losses and still searching for answers about the attacker's motives.

An 8-year-old and 10-year-old were killed in the mass shooting at Annunciation Catholic Church, which includes a school for grades preschool through 8th, the morning of Aug. 27. Another 18 people were injured, including 15 children and three parishioners in their 80s, authorities said.

The children killed were identified by family and media outlets as Fletcher Merkel, 8, and Harper Moyski, 10.

The shooter fired dozens of rounds through stained-glass windows toward children sitting in pews during a service to celebrate the return to the school year. Investigators said 23-year-old Robin Westman was "obsessed with the idea of killing children" and expressed hatred toward several groups in writings being combed through. They have not yet identified a motive.

The FBI said it is is investigating the shooting as an "act of domestic terrorism and a hate crime targeting Catholics."

New details released in investigation

On Aug. 28, authorities in Minneapolis released more information about the investigation into the shooting.

They recovered a total of 116 rifle casings, three shotgun shell casings and one live pistol round at the scene of the shooting, according to the update. Further investigation using surveillance footage suggests that the shooter did not enter the church building. Earlier, authorities said the shooter might have gone inside.

The church's regular practice of locking the doors after Mass began "likely prevented a worse incident," the update said. The suspect attempted to barricade a door from the outside to prevent people from exiting the church.

Authorities comb through hundreds of pages of writings

Investigators were looking through evidence for a potential motive, including hundreds of pages of writings, videos and posts on social media.

The killer left behind detailed plans for the attack and praised other mass shooters in the writings, according to Joseph Thompson, acting U.S. attorney for the District of Minnesota. Westman expressed "hate towards almost every group imaginable," Thompson said.

"In short, the shooter appeared to hate all of us," said Thompson, calling the writings "horrific" and "vile." Westman "saw the attack as a way to target our most vulnerable among us," Thompson said on Aug. 28.

YouTube videos posted from an account linked to the shooter show weapons with racist, homophobic, antisemitic and other hateful scrawlings on them. The writing on the weapons included references to other mass shooters and a threat against President Donald Trump.

Minneapolis mourns victims, prays for injured

Dozens gathered at another church on Aug. 28 for a candlelight vigil, the day after the Annunciation slayings rocked the community on the heels of a shocking 24 hours of repeated fatal shootings in the city. Others mourned outside Annunciation, embracing in tears and holding signs. One read: "You are important."

Family members of the victims began identifying their loved ones.

Jesse Merkel, father of 8-year-old Fletcher Merkel, called the suspected shooter a "coward" who took his son’s life.

"Please remember Fletcher for the person he was and not the act that ended his life," Jesse Merkel said. "Give your kids an extra hug and kiss today. We love you, Fletcher. You'll always be with us."

The family of Harper Moyski, 10, identified her as the second child killed in a statement to CBS News and KSTP-TV.

"Harper was a bright, joyful, and deeply loved 10-year-old whose laughter, kindness, and spirit touched everyone who knew her," the family said in the statement.

Catholic schools in Minnesota asked for more safety funding

Years before the shooting in Minneapolis on Aug. 27, religious and education leaders in the city pleaded for additional state funding to keep their campuses safe.

They never got it. The reasons why are complicated: For one, the state legislature never passed the bill that would've enacted the funding (public schools didn't get the money, either). Lawmakers reintroduced the legislation this year, and it's still pending.

The situation highlights another dynamic in American schools: the idea of investing public money in non-public schools, particularly religious ones, often stokes controversy. In the meantime, no school, public or private, seems entirely free from the risk of a shooting. That fact has prompted some private school leaders to push for security resources on par with their public school counterparts.

"Funding and grant programs should be structured to ensure equitable access for all schools, public and nonpublic, including faith-based schools," said Steven Cheeseman, the president of the National Catholic Educational Association, "so that every student benefits from the resources necessary to ensure that they can attend school in a safe and secure environment."

In a statement to USA TODAY, Gov. Tim Walz's office said private schools in Minnesota already get some state funding. They're also eligible for school safety center resources, including training. Read more here.

-Zachary Schermele

What do we know about the shooter?

Authorities said Robin Westman used a rifle, a pistol and a handgun – all legally and recently purchased – to fire through the windows of the church from the outside of the building, then died by suicide at the rear of the church. More of Westman's firearms were uncovered during property searches.

Westman was a former student at Annunciation Catholic School, local police confirmed on Aug. 28. A former classmate described Westman as an "odd kid" who was "trying to make friends."

Westman's mother, Mary Westman, previously worked at the church, according to posts on Annunciation's website and social media page.

Westman was transgender, authorities said, and court records show that Mary Westman signed a petition to change her name in 2019, saying the "minor child identifies as a female and wants her name to reflect that identification." The change was approved in 2020 when Robin Westman was 17. Minneapolis Mayor Jacob Frey at a news conference, spoke against people using the shooting "to villainize our trans community."

Contributing: Thao Nguyen, John Bacon, Corey Schmidt, Christopher Cann, Sam Woodward, Kinsey Crowley, Eduardo Cuevas, Karissa Waddick and Michael Loria

This article originally appeared on USA TODAY: Search for answers after Minneapolis church shooting continues. What we know

Reporting by Jeanine Santucci, USA TODAY / USA TODAY

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