Texas elementary school shooting echoes the Sandy Hook massacre

The U.S. is once again reeling from a shocking act of violence in an elementary school — an institution where the most innocent are supposed to feel safe.

Nearly 10 years after the Sandy Hook massacre in Newtown, Connecticut, one of the most horrific mass shootings in U.S. history, an 18-year-old gunman opened fire at an elementary school in Texas on Tuesday, killing at least 19 students and two teachers, authorities said.

The killings at Robb Elementary School in Uvalde, a town about 85 miles west of San Antonio, recall the agony of other tragedies, such as the shootings at Columbine High School in Littleton, Colorado, in 1999 and Marjory Stoneman Douglas High School in Parkland, Florida, in 2018.

But the violence stirs especially painful memories of Dec. 14, 2012, the day a 20-year-old gunman killed 20 children and six adults at Sandy Hook Elementary School.

In a grim parallel, two senior law enforcement officials told NBC News they were investigating whether the Texas suspect shot his grandmother before the incident. The Newtown gunman shot and killed his mother before he drove to Sandy Hook.

Sandy Hook Promise, a nonprofit organization founded by the parents of victims, reacted to the Texas news on Twitter: "We are devastated about reports that multiple people are dead, including children.

"Our hearts are with the families and community as this tragic story unfolds," the organization added.

The tweet was accompanied by a hashtag: #EndGunViolence.

Democratic politicians and gun control advocates expressed their shock over the Uvalde killings and renewed their calls for legislative action.

"It has been nearly a decade since Sandy Hook and gun safety legislation has been repeatedly blocked," Sen. Amy Klobuchar, D-Minn., tweeted. "Unconscionable."

President Joe Biden, who was vice president at the time of the Newtown killings, addressed the nation Tuesday evening and invoked the Sandy Hook shooting.

"It's been 3,448 days, 10 years, since I stood up at a grade school in Connecticut, where another gunman massacred 26 people, including 20 first-graders at Sandy Hook Elementary School," Biden said. "Since then, there have been over 900 incidents where gunfire was reported on school grounds."

Fred Guttenberg, a gun control advocate whose daughter, Jamie, was killed in the Parkland shooting, fought back tears in a live interview with MSNBC's Nicolle Wallace on Tuesday, expressing his condolences to the parents of the children killed in Uvalde.

"Their world is spinning," Guttenberg said, describing them as people "who right now have to think, 'How am I going to plan a funeral?' Who right now have to think, 'What kind of casket?' Who right now have to think, 'All I did was send them to school.'"