At least 19 children and two adults were killed on Tuesday after a shooting at an elementary school in the US state of Texas, authorities said.
Texas Governor Greg Abbott said the suspect had also died, adding that law enforcement officers shot and killed the 18-year-old shooter.
President Joe Biden ordered flags to be flown at half-staff at the White House, military posts, naval vessels and US embassies as a "mark of respect for the victims of the senseless acts of violence."
Biden, who had just returned from a trip to Asia, delivered an emotional address on Tuesday.
He said he got the news while on his 17-hour flight back to Washington, when "it struck" him that "these kind of mass shootings rarely happen anywhere else in the world. Why?"
"As a nation, we have to ask when in God's name are we going to stand up to the gun lobby?" he said, as Congress has repeatedly failed to pass gun control legislation. The blocking of such bills is largely attributed to pressure from the powerful National Rifle Association lobby.
"It is time to turn this pain into action," Biden said.
What we know about the Uvalde shooting
The shooting took place at Robb Elementary School in the small city of Uvalde. The area is home to around 16,000 people, including a large Latino community. It is around 85 miles (137 kilometers) from San Antonio, near the US-Mexican border.
The suspect, 18, was a local resident of the town, according to the Texas Department of Public Safety.
Authorities said the gunman first shot and wounded his grandmother before fleeing the scene. He later crashed his car at the elementary school and eventually entered the building wearing tactical gear and carrying a rifle.
The victims died in the shooting were all killed in a single area — a fourth-grade classroom — where the suspect barricaded himself, authorities told US media on Wednesday.
The gunman "just began shooting numerous children and teachers that were in that classroom, having no regard for human life. … Just began shooting anyone that was in his way," Lt. Christopher Olivarez, a spokesperson with the Texas Department of Public Safety said.
Law enforcement officers were later able to force their way into the classroom, shooting and killing the gunman.
Authorities are still working on determining the motive behind the shooting. It remains unclear how many people were injured, although officials said there were "several" wounded.
Official information on the victims has not yet been released, although local media and family members have said the two adults killed were fourth-grade teachers.
'Another Sandy Hook'
Tuesday's shooting was one of the deadliest attacks at a US grade school since 28 people were killed in Sandy Hook, Connecticut, almost a decade ago.
"It's been 10 years since I stood up in a grade school in Connecticut… since then, there have been more than 900 incidents of gunfire reported on school grounds," Biden said.
"We have another Sandy Hook on our hands," said US Senator Chris Murphy of the state of Connecticut. "Our kids are living in fear, every single time they set foot in a classroom, because they think they're going to be next," he added.
The attack came less than two weeks after a white gunman shot and killed 10 Black people at a supermarket in the second-largest city in the state of New York, Buffalo.
The US has suffered recurring mass-casualty shootings and gun violence. According to data from the Centers for Disease Control and Prevention (CDC), 19,350 firearm homicides were reported in 2020, up nearly 35% compared to the year before.
The mass shooting in Uvalde comes days before the National Rifle Association's annual convention is due to open in Houston. Texas Governor Abbott, along with both US Senators from Texas are among Republican officials scheduled to speak Friday during a leadership forum.
'I've had enough!' — US basketball world leads searing response
The head coach of the Golden State Warriors, Steve Kerr, who was in Dallas on Tuesday night to play the Mavericks, seeking a spot in basketball's NBA Finals, refused to answer questions on the game in his pre-match press conference.
"In the last 10 days, we've had elderly Black people killed in a supermarket in Buffalo, we've had Asian churchgoers killed in southern California, and now we have children murdered at school. When are we going to do something?" he asked, before calling on US senators to reconsider a draft law on background checks for gun purchases called H.R.8 that has passed the House of Representatives twice in recent years.
"We are being held hostage by 50 senators in Washington who refuse to put it to a vote despite what we, the American people, want," Kerr said.
His opposing head coach, Jason Kidd of the Mavericks, also declined to answer questions on basketball, saying these things were not at the forefront of his mind even before the crucial game. The WNBA's Dallas Wings issued a statement saying, "Tonight we play for Uvalde."
NBA veteran star LeBron James, meanwhile, asked, "Like when is enough enough man" on Twitter, saying that "these are kids and we keep putting them in harm's way."
The San Antonio Spurs, the closest team to Uvalde, also offered the city its condolences, saying, "There are no right words."
World leaders, including the pope and German Chancellor Olaf Scholz, were swift to offer their condolences.
rs, ar, fb/msh (AFP, AP, dpa, Reuters)