Australian entrepreneur Craig Wright has been identified by tech publications as possibly the mysterious founder of online cryptocurrency Bitcoin, shortly before his Sydney home was reportedly raided in a tax probe Wednesday.

There has long been speculation about who was behind the software written in 2009 under the Japanese-sounding name Satoshi Nakamoto, with various media outlets unsuccessfully trying to find out.

Whoever is behind it likely wants to keep their identify secret as detractors say Bitcoin's use on the underground Silk Road website, where users could buy drugs and guns with it, could link them with criminal activity.

Technology-focused websites Wired and Gizmodo have now both suggested Wright was responsible, saying he fit the creator's profile in nearly every detail, citing leaked documents.

"The signs point to Craig Steven Wright, a man who never even made it onto any Nakamoto hunters' public list of candidates, yet fits the cryptocurrency creator's profile in nearly every detail," said Wired of its investigation.

"Despite a massive trove of evidence, we still can't say with absolute certainty that the mystery is solved.

"But two possibilities outweigh all others: Either Wright invented Bitcoin, or he's a brilliant hoaxer who very badly wants us to believe he did."

On Wednesday, police raided a home in Sydney where Wright reportedly lived with his family.

The Guardian Australia said police forced open the property with staff wearing white gloves seen from the street searching the cupboards and surfaces of the garage.

"The Australian Federal Police can confirm it has conducted search warrants to assist the Australian Taxation Office at a residence in Gordon, Sydney," police said in a statement, without confirming it belonged to Wright.

"This matter is unrelated to recent media reporting regarding the digital currency Bitcoin."

The Australian Tax Office did not comment, citing confidentiality.

- Secret identity -

Gizmodo reported that Wright and Dave Kleiman, an American computer forensics expert who died in 2013, were both involved in the development of the digital currency.

It cited hacked emails and other documents, passed to its website, apparently showing Wright making repeated claims to being Satoshi Nakamoto over a period of years.

None of the details could be verified by AFP.

Tech entrepreneur Zhenya Tsvetnenko, who exchanged emails and then met Wright in Sydney about a possible business venture, said Wright was smart and knowledgeable enough to be Bitcoin's mastermind.

"He was a very mysterious type of guy, he didn't say a whole lot," he told AFP, adding that he was "ultra intelligent".

"The reason why I say it's not out of the question is he was in Bitcoin from the very beginning. I'm not sure he would like me saying that."

Tsvetnenko said Wright was not only adamant that the cybercurrency's protocol "should be adopted and built up" but he also made a little joke about Bitcoin.

When he asked how much of the virtual currency he had, Wright replied he had enough to buy a pizza. Within the Bitcoin community it is well known that the first ever purchase with the currency was a pizza.

Satoshi Nakamoto was previously floated as the name of the person who originated the ingenious concept and the computer coding behind it. But no one ever saw the presumably pseudonymous creator -- he, she or they only communicated on the Internet.

Last year, Newsweek ran a cover story claiming reclusive engineer Dorian Satoshi Nakamoto was the mystery founder, but the Japanese-American denied any involvement.

Bitcoins are generated by complex chains of interactions among a huge network of computers around the planet, and are not backed by any government or central bank, unlike traditional currencies.

Its initial success has since met with a number of highly publicised setbacks.

One of Bitcoin's biggest exchanges, the Tokyo-based MtGox, shuttered last year after admitting 850,000 coins -- worth $480 million at the time -- had disappeared from its digital vaults.