Twenty-one people, including 19 children and two adults, have been killed and multiple people injured after a shooter opened fire in a school in the Texas city of Uvalde, officials say.
The shooting unfolded at Robb Elementary (primary) School, about 130km west of San Antonio. The shooter, identified as 18-year-old Salvador Ramos, opened fire about midday on Tuesday (local time).
Texas Governor Greg Abbott said Ramos was also apparently shot dead by police officers at the scene. Two of those officers were struck by gunfire, though the Governor said their injuries were not serious.
Abbott earlier told reporters the gunman had "horrifically and incomprehensibly" killed students and at least one teacher.
"It's believed that he abandoned his vehicle and entered into the Robb elementary school Uvalde with a handgun, and he may have also had a rifle but that's not yet confirmed according to my most recent report," Abbott added.
Fifteen children were taken to Uvalde Memorial Hospital after the shooting, ABC News reported.
University Health in San Antonio said on Twitter two patients were also transported to them - one a 10-year-old girl and the other a 66-year-old woman. Both were critically injured, the hospital said.
Authorities said the gunman acted alone and his motive was unclear. Texas Senator Roland Gutierrez told CNN the shooter killed his grandmother before entering the school.
Guitterez said the shooter purchased assault rifles after turning 18.
White House press secretary Karine Jean-Pierre said US President Joe Biden has been briefed on the shooting.
Biden "will continue to be briefed regularly as information becomes available", she added. He was aboard Air Force One, the official presidential plane, returning from a trip to Asia when the shooting happened.
"His prayers are with the families impacted by this awful event and he will speak this evening when he arrives back at the White House," Jean-Pierre said on Twitter.
The White House said Biden was due to speak at 12:15pm (NZ time).
Biden has also ordered US flags be flown at half-staff at the White House and other public buildings "as a mark of respect for the victims".
US Vice President Kamala Harris said the United States must have the courage to take action, to ensure violence like this doesn't happen again.
"Our hearts keep getting broken," Harris said.
The latest episode of gun violence unfolded 10 days after another 18-year-old opened fire with an assault-style rifle at a grocery store in a predominantly Black neighborhood of Buffalo, New York, killing 10 people in what authorities called a racially motivated hate crime.
Monday's rampage was the also the latest in a series of mass school shootings in the US that have shocked the world and fuelled a fierce debate between advocates of tighter gun controls and those who oppose any legislation that could compromise the right of Americans to bear arms.
The shooting in Texas was one of the deadliest at a US school since a gunman killed 26 people, including 20 children from 5- to 10-years old, in a rampage at Sandy Hook Elementary School in Connecticut in December 2012.
In 2018, a former student at Marjory Stoneman Douglas High School in Parkland, Florida, killed 17 students and educators.
Grim chronology of US mass shootings
The US experienced 61 "active shooter" incidents last year, up sharply from the prior year and the highest tally in over 20 years, the FBI reported this week.
Below is a list of recent mass shootings:
- Buffalo, May 14, 2022 - A white gunman killed 10 Black people inside a supermarket in a racially motivated attack. He was charged and remains in jail without bail.
- New York City, April 12, 2022 - In one of the most violent attacks in the history of the transit system in New York, 23 people were injured when a 62-year-old man activated a smoke bomb and opened fire in a subway. He was arrested the next day.
- Oxford, November 30, 2021 - Four students were killed and seven other people were wounded after a teenager opened fire at a high school in Oxford, Michigan.
- Indianapolis, April 16, 2021 - A former FedEx employee who had been under psychiatric care shot eight people dead and injured several others at an Indiana facility of the shipping company before taking his own life.
- LA, March 31, 2021 - Four people were killed, one of them a child, in a shooting at an office building in suburban LA before the suspect was arrested.
- Boulder, March 22, 2021 - A mass shooting at a supermarket in Boulder, Colorado left 10 people dead, including a police officer.
- Atlanta, March 16, 2021 - Eight people, including six women of Asian descent, were shot dead in a string of attacks at day spas in and around Atlanta. A male suspect was arrested.
- Milwaukee, February 26, 2020 - A gunman opened fire at the Molson Coors Beverage Co brewing complex in Milwaukee, killing five co-workers before he committed suicide.
- Dayton, August 4, 2019 - A gunman dressed in body armour opened fire in downtown Dayton, Ohio, killing nine people including his sister. Police officers killed the shooter.
- El Paso, August 3, 2019 - A man fatally shot 22 people at a Walmart store in El Paso, Texas. A statement, believed to have been written by the suspect, called the attack "a response to the Hispanic invasion of Texas". Authorities arrested the shooter.
- Virginia Beach, May 31, 2019 - A disgruntled public utility employee opened fire on co-workers at a municipal building in Virginia, killing 12 people before he was fatally shot by police.
- Aurora, February 15 2019 - A man opened fire at an Illinois factory after being fired, killing five workers before he was slain by police.
- Thousand Oaks, November 7, 2018 - A former Marine combat veteran killed 12 people in a bar in Thousand Oaks, California, a suburb of LA. He then killed himself.
- Pittsburgh, October 27, 2018 - A gunman burst into the Tree of Life synagogue near Pittsburgh and fired on congregants gathered for a Sabbath service, killing 11.
- Santa Fe, May 18, 2018 - A 17-year-old student opened fire at his high school outside Houston, Texas, killing nine students and a teacher, before surrendering to officers.
- Parkland, February 14, 2018 - A former student at Marjory Stoneman Douglas High School in Parkland, Florida, killed 17 students and educators.
- Sutherland Springs, November 5, 2017 - A man thrown out of the US Air Force for beating his wife and child shot 26 people fatally at a rural Texas church where his in-laws worshipped, before killing himself.
- Las Vegas, October 1, 2017 - A gunman opened fire on a country music festival from a 32nd-floor hotel suite, killing 58 people before taking his own life.
- Orlando, June 12, 2016 - A gunman fatally shot 49 people at Pulse, a gay nightclub, before he was shot dead by police.
- San Bernardino, December 2, 2015 - A husband and wife killed 14 people at a workplace holiday party in San Bernardino in Southern California before dying in a shootout with police.
- Roseburg, October 1, 2015 - A gunman stalked onto an Oregon college campus and opened fire, killing nine people before police officers shot him to death.
- Charleston, June 17, 2015 - A white supremacist killed nine Black churchgoers at a church in Charleston, South Carolina. He was sentenced to death.
- Washington, September 16, 2013 - A former Navy reservist working as a government contractor killed 12 people at the Washington Navy Yard. He was shot dead by police.
- Newtown, December 14, 2012 - A heavily armed gunman killed 26 people, including 20 children from five- to 10-years old, in a rampage at Sandy Hook Elementary School in Connecticut.
- Aurora, July 20, 2012 - A masked gunman killed 12 people at a cinema in the Colorado city of Aurora. He received multiple life sentences.
- Fort Hood, November 5, 2009 - An army major and psychiatrist opened fire at a US army base in Texas known as Fort Hood, killing 13 people.
Reuters / Newshub.