Versions have also been available this week on Facebook itself, Twitter and YouTube, The Times says.
Additionally, Eric Feinberg of Gipec, a New York-based organisation that tracks extremist social media content, sent the Herald screen grabs of the gunman's video still being shared on Facebook, Instagram, Twitter and YouTube as of March 27.
Conservative MP Damian Collins, who chairs the digital, culture, media and sport select committee, told The Times, "The fact that this content has been allowed to remain on social media platforms is disgusting. We are consistently told that social media companies are capable of regulating themselves. If ever there were an example to demonstrate that they are not, it is surely this."
And Labour deputy leader Tom Watson, said: "Instagram and its parent company [Facebook] profess to be doing everything they can to rid their platforms of this hateful extremist content but it keeps resurfacing. If they ploughed their full financial might into purging this content I'm sure they could manage it, but for some reason they don't.
"The inaction and irresponsibility of these companies is why politicians of all parties in the UK are resolved to introduce tough new regulation that will bring these internet giants into line."
A spokesman for Facebook said the copies of the gunman's video flagged by the Times have now been removed, and added "In line with our policies we will continue to remove all instances of the video and any praise, support and representation of the events as soon as we become aware."
The gunman's video and manifesto have been classed "objectionable" by NZ's Chief Censor, making them illegal to view or share on pain of a fine of up to $10,000 for individuals or up to 14 years' jail.
Late yesterday, NZ Privacy Commissioner John Edwards said Facebook had told him it has done nothing so far to change its livestreaming since the Christchurch attacks.
Prime Minister Jacinda Ardern has said social networks need to do more to prevent inappropriate material, but has yet to outline or timeline measures.
She told the New York Times earlier this week, "Ultimately, we can all promote good rules locally, but these platforms are global."
Across the Tasman, the government has gone on the front-foot, introducing legislation this week which, if passed, could see companies fined up to 10 per cent of their annual revenue and their executives face up to three years' jail if they fail to remove "abhorrent violent content."
One lobby group, Digital Rights Watch, has called the proposed law-changed kneejerk and rushed, and says it will have unintended censorship consequences.
