The gunman responsible for killing 26 people at the Sandy Hook primary school in Connecticut killed himself as the emergency services closed in on him, according to the state's Governer Dannel Malloy.
Speaking to ABCs 'This Week' on Sunday morning, Gov Malloy said this raised the possibility the Adam Lanza, 20, actually planned an even more horrific massacre but was stopped short.
It has also been revealed that Lanza shot his way into the school through a glass door.
According to the Hartford Courant, he stormed past the first classroom on his route and instead went to substitute teacher Lauren Rousseau's class.
He shot everyone inside including the 14 children who were "huddled and clutching one another in fear".
"There were 14 coats hanging there and 14 bodies. He killed them all," said a police officer.
US president Barack Obama is to travel to Newtown to attend a memorial service later on Sunday.
The news came as police released the names and ages of the victims of one of America's worst school shootings. Six-year-old Dylan Hockley, who is thought to be British, is among the victims.
Twenty children, all first graders aged six or seven, were shot up to 11 times each.
Alongside the eight boys and 12 girls, he also killed six women, including school head Dawn Hochsprung, before turning the gun on himself.
In an online article, Dylan's mother, Nicole wrote of Newtown: "The schools here have been amazing, and the people in my neighbourhood are incredible. Newtown is a wonderful place to live and we're looking forward to being here a long, long time."
Dylan's "devastated" Grandmother, Theresa Moretti, said: "Dylan was a lovely boy. He had dimples and blue eyes and a mischievous grin.
"He loved playing Wii and they had a trampoline in their garden. He loved garlic bread and his brother. We are shattered and will never be the same," reports the Mail on Sunday.
Evidence has been found that could help explain the motives of the lone gunman behind one of the worst mass school shootings in American history, police said on Saturday.
The gunman is believed to be 20-year-old Lanza, who killed his mother Nancy at their home before going on the rampage at the school, although Lt Vance refused to confirm the gunman's identity.
The suspected killer's family was "grieving along with all those who have been affected by this enormous tragedy."
“Our hearts go out to the families and friends who lost loved ones and to all those who were injured,” said father Peter Lanza. "No words can truly express how heartbroken we are. We are in a state of disbelief and trying to find whatever answers we can. We too are asking why. We have cooperated fully with law enforcement and will continue to do so. Like so many of you, we are saddened, but struggling to make sense of what has transpired.”
"Our investigators at the crime scene, the school and secondarily at the secondary crime scene we discussed where the female was located deceased, did produce some very good evidence in this investigation that our investigators will be able to use in hopefully painting the complete picture as to how and more importantly why this occurred," he said.
He also revealed the gunman forced his way into the school.
Lt Vance added: "It is believed he was not voluntarily let into the school at all, that he forced his way into the school but that is as far as we can go on that."