The sun shines over gardens surrounding the Tree of Life Synagogue Thursday, Oct. 24, 2019 in the Squirrel Hill neighborhood of Pittsburgh. Sunday, Oct. 27, marks the one-year anniversary of the deadliest attack on Jews in U.S. history. A virtual remembrance, an overseas concert and community service projects highlight the many plans for commemorating the loss. (AP Photo/Keith Srakocic)

PITTSBURGH (AP) — A virtual remembrance, an overseas concert and community service projects highlight the many plans for commemorating the deadliest attack on Jews in U.S. history on the shooting's one-year anniversary Sunday.

The attack killed 11 worshippers and wounded seven at the Tree of Life synagogue in Pittsburgh's Squirrel Hill neighborhood.

"The key to the day is to remember those who were lost — innocent, beloved, sorely missed pillars of the community," said Stephen Cohen, co-president of New Light, one of three congregations present the day of the attack.

The Tree of Life building has remained closed since the shooting. The three congregations now worship at two nearby synagogues. Last week, Tree of Life leaders unveiled their vision for the damaged building: a rebuilt space for places of worship; memorial, education and social events; and classrooms and exhibitions.

The commemoration's theme is "Remember. Repair. Together." It includes a private Jewish service, studying the portion of the Torah that was to be read when the shooting happened, opportunities to do community service, and a public memorial service.

Several hundred people have registered to volunteer at various community organizations on Sunday, said Adam Hertzman, marketing director of the Jewish Federation of Greater Pittsburgh.

The Clarion Quartet, comprised of Pittsburgh Symphony Orchestra musicians, will perform at a special event in Germany that day. Violist Tatjana Mead Chamis, cellist Bronwyn Banerdt, and violinists Marta Krechkovsky and Jennifer Orchard were invited to play at the American Academy in Berlin during the orchestra's European tour.

Thousands are expected to participate in Sunday's remembrance through Pause With Pittsburgh, a virtual memorial event created by the Jewish Federations of North America.

People who register on the event's website will receive a text message or email at 5 p.m. EDT on Sunday. They will see a two-minute video of the names of the 11 victims, followed by a Jewish prayer of mourning recorded by a cantor in Israel specifically for this commemoration. There also will be a link to a live stream of the public memorial service in Pittsburgh.

Authorities charged Robert Bowers, 47, a truck driver from Baldwin, Pennsylvania, in the massacre. Investigators say he used an AR-15 rifle and other weapons, and posted criticism of an immigrant aid society on social media before the attack, claiming the Jewish charity "likes to bring invaders that kill our people." Police said Bowers also raged against Jews as he gunned down his victims.

Federal prosecutors are seeking the death penalty. Bowers' attorneys said this month that the case would be over by now if the prosecutors had accepted his offer to plead guilty in return for a sentence of life in prison without parole. Some congregation members oppose making it a capital punishment case.

Augie Siriano, the Tree of Life's long-time custodian, survived the shooting after seeking shelter. He visited the building a few weeks ago and said he was heartbroken at what he saw: bullet holes, doors off their hinges or shattered, and broken glass.

"They were looking at me, asking, 'Are you OK?' I was in shock," he said. "It's really a shame for some reason he targeted that specific synagogue. It is just something I will never forget."

A sign marking the day of the shooting that killed 11 worshippers and wounded seven others at this synagogue hangs on one of the remaining barricades around the Tree of Life Synagogue, Thursday, Oct. 24, 2019 in the Squirrel Hill neighborhood of Pittsburgh. Sunday, Oct. 27, marks the one-year anniversary of the deadliest attack on Jews in U.S. history. A virtual remembrance, an overseas concert and community service projects highlight the many plans for commemorating the loss. (AP Photo/Keith Srakocic)
Visitors walk through the screens displaying artwork from school students surrounding the Tree of Life Synagogue Thursday, Oct. 24, 2019 in the Squirrel Hill neighborhood of Pittsburgh. Sunday, Oct. 27, marks the one-year anniversary of the deadliest attack on Jews in U.S. history. A virtual remembrance, an overseas concert and community service projects highlight the many plans for commemorating the loss. (AP Photo/Keith Srakocic)
The stars with the names of victims, and other tributes that were placed around the Tree of Life Synagogue after the shooting that killed 11 worshippers and wounded seven others last year, are displayed in the closed entrance Thursday, Oct. 24, 2019 in the Squirrel Hill neighborhood of Pittsburgh. Sunday, Oct. 27, marks the one-year anniversary of the deadliest attack on Jews in U.S. history. A virtual remembrance, an overseas concert and community service projects highlight the many plans for commemorating the loss. (AP Photo/Keith Srakocic)
Judah Samet walks around the Tree of Life Synagogue, Thursday, Oct. 24, 2019 in the Squirrel Hill neighborhood of Pittsburgh. Samet, a holocaust survivor, was in the parking lot of the synagogue last year, when a gunman entered the building and opened fire, killing 11 and wounding seven. Sunday, Oct. 27, marks the one-year anniversary of the deadliest attack on Jews in U.S. history. A virtual remembrance, an overseas concert and community service projects highlight the many plans for commemorating the loss. (AP Photo/Keith Srakocic)
Augie Siriano, the long-time custodian at the Tree of Life Synagogue, stands outside the Rodef Shalom Temple, Thursday, Oct. 24, 2019 in Pittsburgh where he now works. Siriano was in the Tree of Life synagogue last year, when a gunman entered the building and opened fire, killing 11 and wounding seven. Sunday, Oct. 27, marks the one-year anniversary of the deadliest attack on Jews in U.S. history. A virtual remembrance, an overseas concert and community service projects highlight the many plans for commemorating the loss. (AP Photo/Keith Srakocic)
FILE - In this Saturday, Nov. 3, 2018 file photo, The signs for the Tree of Life Synagogue is shown on the building in Pittsburgh. Community service projects, an overseas concert and a virtual remembrance are among multiple ways the deadliest attack on Jews in U.S. history will be commemorated. Sunday marks the one-year anniversary of the shooting at the Tree of Life synagogue in Pittsburgh that killed 11 worshippers and injured seven.  (AP Photo/Keith Srakocic, File)
FILE - In this Saturday, Nov. 3, 2018 file photo, Pittsburgh Police direct traffic as their vehicles close the street adjacent to the Tree of Life Synagogue as a curbside Shabbat morning service is held on the street corner in the Squirrel Hill neighborhood of Pittsburgh. Community service projects, an overseas concert and a virtual remembrance are among multiple ways the deadliest attack on Jews in U.S. history will be commemorated. Sunday marks the one-year anniversary of the shooting at the Tree of Life synagogue in Pittsburgh that killed 11 worshippers and injured seven.  (AP Photo/Gene J. Puskar, File)
FILE - In this  Saturday, Nov. 3, 2018 file photo, Rabbi Chuck Diamond, center, arrives on the street corner outside the Tree of Life Synagogue in the Squirrel Hill neighborhood of Pittsburgh to lead a Shabbat morning service, a week after 11 people were killed and six wound when their worship was interrupted by a gunman's bullets. Community service projects, an overseas concert and a virtual remembrance are among multiple ways the deadliest attack on Jews in U.S. history will be commemorated. Sunday marks the one-year anniversary of the shooting at the Tree of Life synagogue in Pittsburgh that killed 11 worshippers and injured seven. (AP Photo/Gene J. Puskar, File)