Pope Leo, the first U.S.-born pontiff, prayed Sunday for the victims of the deadly shooting rampage in a Minneapolis church and called for an end to the "pandemic of arms ... which infects the world."

Leo, speaking to a crowd gathered in Rome's St. Peter's Square, switched from Italian to English when discussing the Aug. 27 shooting at the Church of the Annunciation.

“We include in our prayers the countless children killed and injured every day around the world,” the pope said. “Let us plead with God to stop the pandemic of arms, large and small, which infects our world.”

Fletcher Merkel, 8, and Harper Moyski, 10, were killed and 15 children and three adults were wounded in the lone gunman's attack at a Mass celebrating the start of the school year. Robin Westman, 23, who died of a self-inflicted gunshot wound, left behind documents expressing hatred of multiple groups and appeared "obsessed with the idea of killing children," authorities said.

The pope prayed that the Virgin Mary would help humanity fulfill the prophecy of Isaiah: “They shall beat their swords into ploughshares and their spears into pruning hooks.”

City providing access to mental health services

The City of Minneapolis opened a Neighborhood Community Support and Resource Center on Sunday to provide "tangible support and resources" for those affected by the shooting. The center, which will remain open through Tuesday, will serve all residents, whether or not they have a direct connection to the tragedy.

The city said in a statement the center will provide access to mental health services, therapy animals, water and snacks, toys and games for kids as well as applications for financial assistance through the Minnesota Crime Victims Reimbursement Program.

“In the wake of this horrific tragedy, our City is grieving alongside the families, neighbors and students whose lives have been forever changed. No one should have to navigate this kind of pain alone,” Mayor Jacob Frey said. “Minneapolis is strongest when we show up for one another, and right now our community needs exactly that.”

Priest hoped to block bullets, protect kids

In Minneapolis, Annunciation began holding Masses this weekend, the first since the shooting. All the Masses were being held in an auditorium at the Annunciation Catholic School next to the church.

The Rev. Dennis Zehren was celebrating Mass on Wednesday when the tragedy unfolded. He said he would reflect on those moments for the rest of his life.

“If I could have got between those bullets and the kids, that’s what I was hoping to do," Zehren, fighting back tears, told NBC News before Mass on Saturday. “The voices cried out 'Down, down, get low. Stay down. Stay down. Don’t get up.'”

Zehren said parishioners were experiencing their darkest hour and lauded them for their "outpouring of love and light and hope.”

Parishioner optimistic church community will rebuild

Annunciation parishioner Sean O’Brien, his wife, Mallory, and their four children were at the Saturday Mass. Sean O’Brien told the Catholic news service OSV News that he was at the Mass on Wednesday, sitting with their 2-year-old daughter. Their fourth and first graders were in the pews with their classes. and their preschooler was in the church basement. None of them were wounded in the assault.

“I came in here optimistic that this community would rebuild, and I now have never been more certain of anything in my life,” he told OSV. “I can’t wait to see what the Lord will do now.”

Mystery surrounds shooter's motive

Authorities have combed through a trove of evidence to uncover a potential motive for the tragedy. Investigators have examined writings and online posts, searched residences in the area tied to the shooter and conducted interviews, court records newly obtained by the St. Cloud Times, part of the USA TODAY Network, show.

In the records, investigators described the blood-soaked scene inside Annunciation Catholic Church. Over 100 bullet casings were found. An AR-15-style rifle, a 12-gauge shotgun and a 9mm pistol were all found with additional ammunition on the suspect's body. Authorities also reviewed Westman's hate-filled writings.

"The shooter appeared to hate all of us," said Joseph Thompson, acting U.S. attorney for the District of Minnesota. He described the writings "horrific" and "vile" and said Westman "saw the attack as a way to target our most vulnerable among us."

− Jeanine Santucci

This article originally appeared on USA TODAY: Pope prays for Minnesota shooting victims; church holds first Masses since tragedy

Reporting by John Bacon, USA TODAY / USA TODAY

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