Lanza's Father Wishes Son Had Never Been Born

The father of Sandy Hook Elementary School shooter Adam Lanza has said he believes his son would have killed him "in a heartbeat" if given the chance.

In his first comments since the 2012 massacre, Peter Lanza also said he wishes his son had never been born.

The shooting at the Newtown school left 20 children and six teachers dead.

Lanza killed his mother on his way to the school, and then shot himself in the mouth as police arrived at the scene.

"With hindsight, I know Adam would have killed me in a heartbeat, if he'd had the chance," Peter Lanza told The New Yorker magazine.

"I don't question that for a minute."

He said he believed the reason why Lanza shot his mother Nancy four times is "one for each of us: one for Nancy; one for him; one for (brother) Ryan; one for me".

Peter Lanza said he now wishes his son had never been born, and that he cannot think of him outside of his action on December 14, 2012.

"That didn't come right away. That's not a natural thing, when you're thinking about your kid.

"But, God, there's no question."

The massacre shocked America and rekindled a debate over gun control.

Over what the magazine said were six lengthy interviews, Peter Lanza described his son's upbringing, saying he had been diagnosed with Asperger's Syndrome, though the boy refused to accept it.

But he did not see the condition as the cause of his son's actions.

"Asperger's makes people unusual, but it doesn't make people like this," he said.

When his son reached middle school, Peter Lanza said, he stopped being a "normal, weird little kid" and started showing signs that "something was wrong".

"The social awkwardness, the uncomfortable anxiety, unable to sleep, stress, unable to concentrate, having a hard time learning, the awkward walk, reduced eye contact," he said.

"You could see the changes occurring."

Peter Lanza also opened up about his grief dealing with the aftermath of the tragedy, saying not one hour goes by that he does not think about it.

He spoke of his relationship with his son, whom he had not seen for two years by the time of the massacre.

"Any variation on what I did and how my relationship was had to be good, because no outcome could be worse," he said.

"You can’t get any more evil."

"How much do I beat up on myself about the fact that he's my son?

"A lot."

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