THEY'RE said to be the darkest places on the internet, where users pay thousands to watch rapes and murders live.
But who's responsible for the dark web's notorious "red rooms", and are they real or an urban myth?
What is a red room?
Red rooms are rumoured online spaces within the dark web, the shadowy underbelly of the internet, used to hide illegal activity online.
According to online reports, they're murky spots where sickos can pay to watch live streamed videos, of rape, torture, murder, and worse.
Users are said to pay thousands, or even tens of thousands, for access to the dark clips.
Urban legends surrounds red rooms have circulated for years, but so far no evidence has emerged that they exist.
Their name is thought to have originated from the 1983 horror film Videodrome, where torture is shown live on TV in a red-painted room.
Alternatively, it's been suggested the phrase arose from "Red Rum", which spells "murder" backwards.
Are red rooms a myth?
While red rooms have generated plenty of discussion on social media over the years, there's no evidence that they exist.
Even if they had cropped up in some grim corner of the internet, it's not clear how anyone could run one.
Tor – the special web browser needed to access the dark web – couldn't run the rooms, as it's too slow to support live-streamed video.
Other secretive browsers would also struggle to host the streams, as they run their web traffic through multiple servers.
One case that suggests there might be sites where people pay to view disturbing, illegal content is that of depraved paedophile Peter Scully.
The former property developer would entice impoverished children with money and gifts back to his home in the Philippines.
He then drugged the vulnerable youngsters and made films of him raping and torturing them for an international paedophile ring.
Operating a secret child pornography site on the Dark Web, he sold the videos for up to $10,000 per view.
In one sickening case, Aussie sex attacker Scully, 57, dubbed one of the world’s worst paedophiles, made two little girls dig their own graves.
What is the dark web?
The internet is actually made up of three different layers: the surface web, the deep web and the dark web.
The top layer, the surface web, are web pages that show up using search engines such as Google - like The Sun website that you're looking at right now.
The deep web are web pages which search engines can't access and are therefore hidden, accessed via passwords and authorisation.
Any time you log into an account you're accessing deep web content that won't show up on a search engine.
For example, work intranets, password-protected areas of online banking and draft blog posts are all stored on the deep web.
This means that if someone was to Google your name, your banking information or Amazon wishlist won't show up in the results.
The dark web is a network of untraceable online activity and websites on the internet. They cannot be found using search engines and to access them you need to use specific software, configurations or have authorisation. They are used by lots of different people to keep their web activity hidden.
Where did the dark web come from?
The dark web was actually created by the US government to allow spies to exchange information completely anonymously.
US military researchers developed the technology, known as Tor (The Onion Router) in the mid-1990s and released it into the public domain for everyone to use.
The reason was so that they could stay anonymous - it would be harder to distinguish the government's messages between spies if thousands of other people were using the same system for lots of different things. Tor now hosts roughly 30,000 hidden sites.
It's called The Onion Router because it uses the technique of onion routing - making websites anonymous through layers of encryption. Most websites are also hosted on the .onion domain.
What is the government doing about the dark web?
On April 11, Home Secretary Amber Rudd launched a multi-million pound cyber blitz on criminals selling guns on the dark web.
She announced a £9million fund to ensure every police force in the UK has a dedicated cyber crime unit to bust its "sickening shopping list of services and products".
The extra cash will tackle offenders who are exploiting the anonymity of the dark web - where users use freely available software to avoid being tracked - to trade in guns, drugs and child abuse images.
This anonymity has attracted criminals seeking to avoid detection by law enforcement agencies.
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In other news, hackers are flogging Brits’ Deliveroo, Tesco and McDonald’s accounts on the Dark Web for as little as 42p.