In December 2012, Adam Lanza stormed a primary school in the town of Newtown in Connecticut, US, and killed 20 young school children and 6 members of staff.
He had come from his house where he had shot dead his own mother, Nancy.
Adam used firearms that he had collect during his descent into a dark madness and after committing the terrible crimes he turned the gun on himself.
In his first interview since the tragedy, Adam’s father Peter has spoken out about his infamous son.
‘With hindsight, I know Adam would have killed me in a heartbeat, if he'd had the chance,’ he said. ‘The reason he shot Nancy four times was one for each of us: one for Nancy; one for him; one for (his brother) Ryan; one for me.’
Distraught Peter told New York Magazine: ‘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.’
‘I do not even like to say my name,’ he added.
Peter is also dad to son Ryan, who is now not only coming to terms with what his brother has done but is also coming to terms with the loss of his mother.
Peter believes that Adam was suffering from a mental disorder, possibly schizophrenia.
‘The social awkwardness, the uncomfortable anxiety, unable to sleep, stress, unable to concentrate, having a hard time learning, the awkward walk, reduced eye contact.’
'Asperger's makes people unusual, but it doesn't make people like this,’ he added.
Since the terrible events in Sandy Hook, Mr Lanza has been sent items from strangers such as cuddly toys with messages such as ‘My First Christmas in Heaven.’
He decided to speak out as he ‘wanted people to be afraid of the fact that this could happen to them.’