Twenty-seven people, including 20 children, were killed on Friday in a shooting at a Connecticut elementary school.
The violent attack in Newtown, Conn., is one of the worst mass shootings in U.S. history and has reopened the divisive political debate over gun control.
According to reports, the gunman carried a .223 caliber rifle and a handgun. Law enforcement authorities were continuing to identify victims at the school.
Multiple news outlets identified the gunman as Adam Lanza, 20, of Hoboken, N.J., who was dead at the scene.
According to Lt. J. Paul Vance of the Connecticut State Police, who gave a short briefing on the incident Friday afternoon, 18 children died in the school, two children died after being taken to the hospital. Six adults and the shooter died at the school, and one other adult was dead at what Vance called "a secondary crime scene."
According to multiple media reports, Lanza allegedly killed his mother, a kindergarten teacher Sandy Hook Elementary, at their home before driving to the school.
Late Friday, Vance told reporters that a list of victims’ names would be released when positive identifications are complete, perhaps on Saturday morning.
In his final briefing of the day, Vance said first responders “saved a lot of lives.”
President Obama on Friday ordered all American flags be flown at half-staff until sunset on Dec. 18 “as a mark of respect for the victims of the senseless acts of violence.”
Obama addressed the nation on the incident at 3:15 p.m.
“Our hearts are broken today,” Obama said, fighting back tears.
In comments at the White House, the president said the nation has “endured too many of these tragedies,” adding that “meaningful action” is needed.
He said that there’s not a parent in America who doesn’t feel the same “overwhelming grief” that he does.
Responding to Obama's press conference, Dan Gross, president of the Brady Campaign to Prevent Gun Violence, said his organization was moved by Obama's comments.
"We were moved by President Obama's raw emotion during his remarks today," Gross said. "We are committed to working with him to channel it into the change that is too long overdue."
The campaign has been critical in the past of Obama.
House Speaker John Boehner's (R-Ohio) office announced there would be no weekly Republican address Friday evening "so that President Obama can speak for the entire nation at this time of mourning."
The killings are the latest in a year marked by mass shootings.
In July, a gunman killed 12 people and wounded 58 others at a showing of "The Dark Knight Rises" in an Aurora, Colo., movie theater. A few weeks later, another gunman killed six people and himself at a Sikh temple in Milwaukee.
None of these shootings has altered the debate in Washington over gun control, where neither the White House nor congressional leaders have made altering gun laws a priority.
White House spokesman Jay Carney declined to answer questions about gun control, saying today was not the day to have that discussion. He emphasized that the White House was awaiting more information from Connecticut.
“I think it’s important on a day like today to feel enormous sympathy for the families that were affected and to do everything we can to support state and local law enforcement and support those who are enduring. There will be a day for discussion of the usual Washington policy debates,” he said. “But I don’t think today is that day.”
But Rep. Jerrold Nadler (D-N.Y.) shot back at the White House's claim that it was too soon to start a discussion on gun control.
"We cannot simply accept this as a routine product of modern American life," he said in a statement. "If now is not the time to have a serious discussion about gun control and the epidemic of gun violence plaguing our society, I don’t know when is. How many more Columbines and Newtowns must we live through? I am challenging President Obama, the Congress, and the American public to act on our outrage and, finally, do something about this.”
In addition, a petition went online Friday from a group that identified itself as "people affected by gun violence — parents, family, friends," to organize a demonstration outside the White House to tell the president "today is the day" to discuss gun control.
Lawmakers from Connecticut quickly expressed sorrow over the violence in their home state.
“I am shocked and saddened by the horrific news from Sandy Hook Elementary School this morning, and I pray that kids, teachers, staff and families reach safety as quickly as possible,” said Connecticut Rep. and Sen.-elect Chris Murphy (D) in a statement. “While we don’t have much information right now, our thoughts are with the victims and their loved ones.”
— Daniel Strauss contributed to this report.
— Posted at 12:42 p.m. and last updated at 9:16 p.m.