A reported 21 people were killed in an attack by a lone gunman at an elementary school in the small town of Uvalde, Texas, on Tuesday. Of the dead are 19 students and two adults. An additional 17 people were injured.
All victims had been identified as of Wednesday.
The gunman was killed by a law enforcement agent.
The attack at Robb Elementary School occurred just two days before summer break was to begin, with the school's calendar listing May 26 as the last day of classes. The school teaches students in grades two through four, and around 600 students attend.
Here's what else we know.
Uvalde is a small community
Uvalde, Texas, is a community of around 16,000 people, most of whom are Hispanic, according to U.S. Census Bureau data. The town sits about 85 miles west of San Antonio.
It's the kind of place where "interconnections are thick" and no one would have expected a mass shooting at the local school, Marc Duvoisin, the editor-in-chief of the nearby San Antonio Express-News, told NPR.
Uvalde is also best known as the hometown of Oscar winner Matthew McConaughey. The actor took to social media to share his heartbreak over the tragedy.
In a lengthy statement, he offered prayers to those impacted and urged Americans to reassess their values, saying, "we have tragically proven that we are failing to be responsible for the rights our freedoms grant us," without specifically mentioning guns or reforms.
The shooter was from Uvalde
The 18-year-old gunman, Salvador Ramos, had attended Uvalde High School, which had its graduation day set for this coming Friday. At some point, however, he had dropped out, officials said.
There had been no evidence of mental health issues prior to the violence Tuesday. Investigators said there is also no evidence of a criminal record, though research is being done into whether the gunman had a record as a juvenile.
Law enforcement said the shooter acted alone, but more details have since emerged about his activity in the hours before the shooting.
He shared private messages on Facebook with someone and told the person he intended to shoot his grandmother. Police confirm he did attack his grandmother and shot her in the face. She survived and is in the hospital.
After shooting her, he returned to Facebook to send a message confirming what he did. He then posted in the chat that he was targeting an elementary school next but didn't mention Robb Elementary School specifically.
He took off in his grandmother's car, later crashing it not far from Robb Elementary School. He then approached the school, encountered a school resource officer (though no gunfire was exchanged) and entered through a back door on campus.
Texas state Sen. Roland Gutierrez told CNN on Tuesday evening, following a briefing from the Texas Rangers, that the shooter bought at least two assault rifles shortly after his 18th birthday.
"He had no problem accessing those weapons," Gutierrez said during the interview.
A Border Patrol agent shot the gunman
After the gunman gained entry to the school, police from various departments gathered to form a tactical unit.
A Border Patrol tactical unit responded to the scene, and one of its agents shot and killed the suspect, according to a source with the agency.
The school year is over and other events canceled
Graduation for the local high school is postponed for now, according to the superintendent of the Uvalde Consolidated Independent School District, Hal Harrell. He spoke during a second news conference Tuesday.
Harrell clarified that the district's school year is done, following the shooting, and that all other events are canceled.
He said grief counseling was going to be provided for students and their families starting Wednesday morning at the local civic center.
Local hospitals and the public respond to the need
Uvalde Memorial Hospital established an emergency command center after hearing word about the attack from law enforcement. The response following the shooting was "enormous," and additional staff came on to assist, according to a news release from Uvalde Memorial.
The hospital treated 15 people (11 of whom were children) following the shooting at Robb Elementary. Two children received by the hospital were dead on arrival.
Four young patients had to be transferred to trauma centers in San Antonio for further treatment. Seven children were able to be sent home following treatment.
Early Tuesday evening, local hospitals and other organizations put out a call for blood donors to respond to the tragedy, and the public has responded in a major way.
South Texas Blood & Tissue said a huge number of donors allowed it to send 15 units of blood to the school and local hospitals immediately after the shooting and another 10 to an area hospital later in the day.
The organization also said further appointments to donate were largely booked, but it encouraged people to continue to donate.
GoFundMe has established an online hub of verified fundraisers supporting victims and loved ones affected by the shooting.
Robb Elementary School has also created a fundraising account at a local bank to assist families. It is accepting checks and online payments.
Biden and politicians respond
President Biden ordered flags to be flown at half-staff at the White House and other government buildings following news of the tragedy.
Biden addressed the nation Tuesday night following the shooting.
"How many scores of little children who witnessed what happened — see their friends die as if they're on a battlefield, for God's sake," he said.
He plans to travel to Texas in the coming days to meet with families affected by the mass shooting.
Leaders from around the world spoke out. Pope Francis called for stricter gun control in the United States. Others, including Ukrainian leaders, sent their condolences.
Sen. Chris Murphy, D-Conn., took to the Senate floor hours after news of the shooting broke. Newtown, Conn., in Murphy's state, is the location of the 2012 Sandy Hook Elementary School shooting, during which 26 people — mostly 6- and 7-year-olds — were killed.
Murphy has aggressively called for gun reform following that incident.
Murphy implored, "What are we doing? Just days after a shooter walked into a grocery store to gun down African American patrons, we have another Sandy Hook on our hands. What are we doing?"
He pleaded with his colleagues to act on gun control legislation now.
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NPR reporter Ayana Archie contributed to this article.