A tearful U.S. President Barack Obama addressed the American public Friday, saying “our hearts are broken” by the school massacre near New York City that left 20 young children and six adults dead. A gunman also died at the scene.

Mr. Obama spoke shortly after ordering U.S. flags at the White House and federal facilities across the country lowered to half-staff, in a traditional presidential gesture of national grief.

His address came hours after horror and mayhem struck at an elementary school in Newtown, Connecticut, a small town 130 kilometers northeast of New York City. “The majority of those who died today were children — beautiful little kids between between the ages of five and 10 years old. They had their entire lives ahead of them…,” the president said.

By mid-afternoon, a Connecticut state police spokesman told reporters the crime scene had been secured. He said the first emergency call came shortly after 9:30 a.m. Police descended on the scene and immediately entered the school. Eighteen of the children and six adults, including the shooter, were found in one section of the school in two separate rooms. Two other children died in area hospitals.

It is widely reported that the 20-year-old suspect's mother — a teacher at the school — was among the dead. Circumstances of her death remained unclear hours after the tragedy. The gunman's 24-year-old brother was undergoing police questioning late Friday.

The president called the shooting a “heinous crime,” and said “as a country we have been through this too many times.” He then listed a string of recent mass shootings, including those at a temple in Wisconsin, a movie theater in Colorado and a shopping mall in Oregon. He said “we're going to have to come together and take meaningful action to prevent more tragedies like this, regardless of the politics.”

Governor Dannel Malloy called the shooting “a tragedy of unspeakable terms.”

Television footage showed children being rushed from the school single file, people hugging, and frantic parents either waiting for world on their children or hugging them once found. It took several hours before the full scope of the tragedy became public.

When it did, reports of heroism surfaced as well. In one widely reported instance, a teacher herded her entire first grade class into a bathroom, locked the door, and cowered alongside the children until help arrived.