Conspiracy theorist Alex Jones has testified that he now understands it was irresponsible of him to declare the Sandy Hook Elementary School massacre a hoax and that he now believes it was “100% real”.

Speaking a day after the parents of a six-year-old boy who was killed in the 2012 attack testified about the suffering, death threats and harassment they have endured because of what Jones has trumpeted on his media platforms, the Infowars host told a Texas courtroom that he definitely thinks the attack happened.

“Especially since I’ve met the parents. It’s 100% real,” Jones said at his trial to determine how much he and his media company, Free Speech Systems, owe for defaming Neil Heslin and Scarlett Lewis.

Newtown Shooting Infowars
Neil Heslin, father of six-year-old Sandy Hook shooting victim Jesse Lewis (Briana Sanchez/Austin American-Statesman via AP)

Their son Jesse Lewis was among the 20 students and six educators who were killed in the attack in Newtown, Connecticut, which was the deadliest school shooting in American history.

But Mr Heslin and Ms Lewis said that an apology would not suffice and that Jones needed to be held accountable for repeatedly spreading falsehoods about the attack. They are seeking at least 150 million dollars.

Closing arguments are expected to begin later on Wednesday after more testimony from Jones, who has portrayed the lawsuit as an attack on his First Amendment rights.

Jones is the only person testifying in his own defence. His lawyer asked him if he now understands it was “absolutely irresponsible” to push the false claims that the massacre did not happen and no-one died.

Jones said he does, but added: “They (the media) won’t let me take it back.”

He also complained that he has been “typecast as someone that runs around talking about Sandy Hook, makes money off Sandy Hook, is obsessed by Sandy Hook”.

Jones’ testimony came a day after Mr Heslin and Ms Lewis told the courtroom in Austin, where Jones and his companies are based, that Jones and the false hoax claims he and Infowars pushed made their lives a “living hell” of death threats, online abuse and harassment.

They led a day of charged testimony on Tuesday that included the judge scolding the bombastic Jones for not being truthful with some of what he said under oath.

In a gripping exchange, Mr Lewis spoke directly to Jones, who was sitting about 10 feet away. Earlier that day, Jones was on his broadcast programme telling his audience that Mr Heslin is “slow” and being manipulated by bad people.

“I am a mother first and foremost and I know you are a father. My son existed,” Ms Lewis said to Jones. “I am not deep state… I know you know that… And yet you’re going to leave this courthouse and say it again on your show.”

At one point, Ms Lewis asked Jones: “Do you think I’m an actor?”

“No, I don’t think you’re an actor,” Jones responded before the judge admonished him to be quiet until called to testify.

Mr Heslin and Ms Lewis are among several Sandy Hook families who have filed several lawsuits alleging that the Sandy Hook hoax claims pushed by Jones have led to years of abuse by him and his followers.

Mr Heslin and Ms Lewis both said they fear for their lives and have been confronted by strangers at home and on the street. Mr Heslin said his home and car have been shot at. The jury heard a death threat sent via telephone message to another Sandy Hook family.