Julian Assange, the founder of whistleblowing website WikiLeaks, has published a mysterious 68-digit code on Twitter that many believe indicates a fresh disclosure is on the horizon.

The string of letters and numbers, which appears to be an encryption key, or hash, sparked a frenzy of speculation across social media, with many claiming that it meant that a new leak about Hillary Clinton was imminent. Others believed it was a so-called "dead man's switch."

Hashes of this nature can be used to verify the transfer of documents or files and are often described as a digital signature. Assange has not commented on its purpose.

WikiLeaks is known to release "insurance files" to torrent websites – batches of material hidden behind a long password known only to a select few people.

A "dead man's switch", also used by NSA leaker Edward Snowden, is a technique in which a password would be released to the public if Assange was in danger.

"Rumour has it that Julian Assange will be dropping those missing Hillary emails tomorrow ... stay tuned," speculated one Twitter user.

A commentator on Reddit resurfaced (debunked) claims from last year that Assange had been killed. "Everything since then is just a cover up," he or she wrote.

After the code, Assange tweeted: "There's something wrong with Hillary Clinton. It is not just her constant lying. It is not just that she throws off menacing glares and seethes thwarted entitlement.

"Watch closely. Something much darker rides along with it. A cold creepiness rarely seen."

He was responding to comments made by Clinton, who is in the UK doing press for her new book "What Happened?" During one interview, she branded WikiLeaks a fork of Russian intelligence and called Assange a "nihilistic opportunist who does the bidding of a dictator."

The work of WikiLeaks, and by extension Julian Assange, often breeds conspiracy.

Last year, as it published the personal emails of John Podesta, a close aide to former presidential candidate Clinton, swarms of social media users (and many, many bots) amplified its posts.

Eager internet detectives – without evidence – have in the past linked its releases to paedophile networks involving politicians and the alleged murder of a Democratic Party staffer. US intelligence believes the website was abused by Russian intelligence to spread fear and propaganda.

julian assange
Julian Assange tweeted a cryptic code and the internet went mad Jack Taylor/Getty Images

In June 2016, WikiLeaks published an 88GB-sized insurance file to the internet. "Protect our coming publications," WikiLeaks' official Twitter account posted at the time.

And later the same year, in October, the website released three "pre-commitment" insurance files via Twitter - titled John Kerry, Ecuador and UK FCO - alongside lengthy 64-digit codes.

Later that month, it was confirmed that Ecuador – the country currently giving Assange political asylum – had severed the internet connection in the embassy where the WikiLeaks founder resides. In recent weeks, Assange has reportedly clashed with Ecuador over his stance on Catalonia.

Adding to the confusion on social media, on the same day the new code was published, Fox News host Sean Hannity tweeted: "JulianAssange HAS THE TRUTH. We deserve the TRUTH."

Despite being confined to the walls of the London embassy, WikiLeaks has continued to publish leaked material. Most recently, the Russian Spy Files and the Vault 7 CIA documents.