Families of America’s gun massacre victims, including those from the Sandy Hook school shooting and the latest rampage in Orlando, are being stalked by conspiracy theorists and “gun truthers” who claim the atrocities never happened.

Grieving parents from the Sandy Hook massacre are being told their children never died or never even existed.

The harassment started within days of the shooting, when a young man armed with a military-style assault rifle ran amok at Sandy Hook elementary school in Connecticut, USA, in December 2012, killing 20 first graders and six teachers.

It continues to this day.

“F*** you!! Your child never died at Sandy Hook,” is one among thousands of online posts that Lenny and Veronique Pozner have had to deal with as they mourn their six-year-old son Noah.

“Where’s Noah going to die next?” is another.

Some “gun truthers” claim Sandy Hook was a government-sponsored stunt aimed at galvanising support for tougher gun laws.

“There are many conspiracies, many theories, one of which is that Noah is an actor and he’s never really died and that we’re all actors,” Mr Pozner told Foreign Correspondent’s Lisa Millar.

Unlike most bereaved parents, Lenny Pozner refuses to ignore the trolls. He dedicates himself to confronting them.

So in a country awash with conspiracy theories — 9/11, JFK, Obama’s backstory — why does he bother?

“I have to absolutely defend the memory of my son — I have no choice,” he said.

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