Twenty-seven people, including 20 children between the ages of five and 10, are confirmed dead in one of the worst mass shootings in U.S. history in Connecticut on Friday morning.

Connecticut state police Lt. Paul Vance said 18 children died at Sandy Hook Elementary School in Newtown and two other children died later in hospital. Six adults were also killed. The shootings occurred in two rooms in one section of the school in the quaint town about 125 kilometres northeast of New York City.

According to a parent at the school, the principal and the school psychologist were also killed. One person – reportedly a teacher who was shot in the foot – was injured and hospitalized.

The suspected gunman, identified by a law enforcement official as Adam Lanza, 20, was among those killed. His cause of death hasn’t been revealed but police say he was found inside the school.

Police also say they have recovered three high-powered guns from the scene. CNN reports that the guns were legally owned by the suspected shooter’s mother.

Lanza’s older brother, Ryan, 24, was questioned by police, The Associated Press reported. He has not been labelled a suspect in the case.

A student described the terror to an NBC affiliate in Connecticut: “I was in the gym and I heard like seven loud booms, and the gym teachers told us to go in the corner and we huddled. We all heard these booming noises, and we started crying. So the gym teachers told us to go into the office where no one could find us. Then a police officer told us to run outside.”

Vance said police first received a call about an incident at the school at around 9:30 a.m.

CNN reports that the gunman’s mother, who taught at the school, was found dead at the Lanza family home in New Jersey.

Vance confirmed that there was a “secondary crime scene…with a deceased adult.”

There were unconfirmed reports of a second shooter, who may have been taken into custody. Vance would only confirm one shooter at this time, although he stressed that the investigation was still “active” and in its early stages.

Vance also said a list of the victims names, including gunman’s, will be made available by police, likely on Saturday.  Police will provide another update Saturday at 8 a.m.

A shaken and emotional President Barack Obama wiped tears from his eyes a handful of times as he addressed the nation.

“We’ve endured too many of these tragedies in the past few years, and each time I learn the news I react, not as a president, but as anybody else would, as a parent,” he said. “And that was especially true today. I know there isn’t a parent in America who doesn’t feel the same overwhelming grief that I do.”

“We are going to have to come together and take meaningful action to prevent more tragedies like this, regardless of the politics.”

“Our hearts are broken today.”

Thousands showed up at a church across town for a 7 p.m. vigil to hear leaders, including Sen. Richard Blumenthal and the governor, address the victims’ families.

Connecticut Gov. Dan Malloy, who met with the victims’ families first, said later, ”On behalf of the people from the State of Connecticut we extend our condolences to the parents of these children as well as the adults.”

In Canada, Prime Minister Stephen Harper tweeted his condolences.

“The news is just awful. The thoughts and prayers of Canadians are with the students and families in CT affected by this senseless violence,” he said.

Toronto Mayor Rob Ford tweeted, “Heartfelt sympathies to the victims & families of the tragic event at a Connecticut school earlier today.”

The school shooting is one of the worst the United States has ever seen. During the 2007 Virginia Tech massacre, 32 people were killed. In the Columbine shooting of 1999, 12 students and one teacher were killed.

There are also been several such shootings around the world.

  • Here in Canada, 14 women were gunned down at the Ecole Polytechnique in Montreal on Dec. 6, 1989, in a gender-based attack. The shooter later killed himself.
  • In Russia, 344 were killed – including 186 school children – during a hostage-taking at Beslan’s School Number One in North Ossetia in 2004.
  • In Ma’alot, Israel, 26 people were killed and 60 were injured as the Democratic Front for the Liberation of Palestine attacked a school in 1974 on the anniversary of Israel’s independence.
  • In the United Kingdom, 16 kindergarten students and their teacher were killed in 1996. The gunman killed himself at the end of the three-minute shooting spree in the small Scottish town of Dunblane.

List provided by Yahoo

With files from CNN