The gunman who shot dead 20 children used a rifle to fire at victims multiple times after forcing his way into Sandy Hook school, a medical examiner and police reveal.

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All 20 child victims of the Connecticut shootings were first graders aged six or seven and some were shot up to 11 times, it has been revealed.

Police in Newtown have released the names of the 26 people killed in the massacre on Friday at Sandy Hook school in Newtown.

Eight of the children were boys and 12 were girls. All six adults killed at the school were women.

Connecticut's chief medical examiner H Wayne Carver II told a press conference all the children killed were shot more than once, with the ones he examined personally shot between three and 11 times.

I have been at this more than a third of a century ... this probably is the worst I have seen. H Wayne Carver II, medical examiner

"Everybody's death was caused by gunshot wounds," he said.

"And obviously the manner of the death in all these cases has been classified as homicide.

"I have been at this more than a third of a century ... this probably is the worst I have seen, or the worst I know any of my colleagues have seen.

He added that all of those people he had examined so far had injuries sustained by shots from a "long weapon", reported to be a rifle.

Librarian's story

Assistant librarian Mary-Anne Jacob told Channel 4 News how she hid from the gunman with a class of older children while the massacre unfolded.

She said: "You could hear it, it was like 'bang, bang, bang'... we had 18 kids with us, a fourth grade, class. They were like 'is this a drill? what's going on?'

"When we realised the door wasn't locked we crawled through the kitchen into a little storage room and locked the doors. There happened to be some crayons in there - so we all started colouring and drawing pictures. And we waited."

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'Forced his way in'

Earlier Lieutenant Paul Vance, Connecticut state police spokesman, said "we have established the [gunman's] point of entry" at Sandy Hook school in Newtown, Connecticut.

"I can tell you he was not voluntarily let into the school at all. He forced his way into the school."

Lt Vance also said that a list of the victims' names would be released later, but pleaded with the media to give grieving families privacy.

"We're going to allow the medical examiner to come in and provide the identities of the shooter - and all the deceased in this investigation," he said.

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And he said police were gathering vital evidence about the attacker who killed 26 people, then himself, inside the primary school on Friday.

It is understood he also shot his mother at home before driving her car to the school.

"Our investigators at the crime scene - the school and secondarily at the secondary crime scene where the female was found deceased - did produce some very good evidence," said Lt Vance.

"This will hopefully paint a complete picture of how and - and more importantly - why this occured."

Connecticut shooting suspect Adam Lanza.

Suspected gunman

An image has been released of the suspected gunman (right).

Adam Lanza, 20, has been described as shy, nervous and "remote". It is reported he had a personality disorder.

It is also reported his brother, Ryan Lanza, 24, who is helping police with their investigation, has told officers he has not been in contact with Adam since 2010. Ryan Lanza was wrongly named as the suspect by US TV networks for a brief time on Friday.

Below: police radio recordings reveal how the tragedy unfolded

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