Journalist Owen Jones stormed out of a live television interview about the mass killing in Orlando in protest at his interviewer's refusal to name the shooting an attack on LGBT people.
"At the end of the day this was a homophobic hate crime, as well as terrorism and it has to be called out, as I have to say, on Sky News and lots of news channels, there's not been many LGBT voices that I've heard myself," he said.
"[...] it is one of the worst atrocities committed against LGBT people in the western world for generations and it has to be called out as such," he added.
Host Mark Longhurst interjected and said the crime had been carried out against "human beings" who were " trying to enjoy themselves, whatever their sexuality."
The interview surrounded the New York-born Omar Mateen who opened fire in a gay nightclub called Pulse on Saturday evening, killing at least 50 people and injuring 53 more.
Mr Longhurst also said Mr Jones could not suggest the Orlando attack was "worse" than the murder of more than 100 people in Paris last November.
Mr Jones fired back that Mr Longhurst "could not understand" as he was not gay. He also said the presenters were trying to "deflect" the homophobic element of the attack.
When co-panelist and journalist Julia Hartley-Brewer suggested that the killer might have taken equal umbrage against her, "a gobby woman", Mr Jones became increasingly exasperated.
"I'm sorry, I just find this the most astonishing thing I've ever been involved in on television," he said.
"If he'd [Mateen had] walked into a synagogue and massacred dozens of Jewish people, you wouldn't be saying what you're saying now."
"You would be talking about it as an anti-semitic attack. This was a deliberate attack on LGBT people."
As the co-panelists moved on to mention a commentator from gay rights group Stonewall, Mr Jones said: "I've had enough of this," took off his microphone and left the set, admitting he was "upset".
The presenters continued to discuss the newspapers' coverage of the killing without Mr Jones.
Ms Hartley-Brewer was accused by MP Diane Abbott of not "realising" how "in denial" of homophobia she appeared to be.
Stonewall held a vigil for the victims in New York City on Sunday.
Orlando also organised a moment of silence for the victims.
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