A copycat version of the Silk Road, the web marketplace for illegal drugs shut down by U.S authorities last month, has appeared online.
The site came online Wednesday and has already posted hundreds of narcotics for sale including marijuana and ecstasy and is accepting the digital currency bitcoin as payment, according to reports from All Things Vice, a blog dedicated to the "dark web" – illegal web activities.
Last month, the mastermind behind the original Silk Road website, Ross William Ulbricht, also known online as "Dread Pirate Roberts", was arrested by the Federal Bureau of Investigation and his website shut down.
But a site administrator using the same Dread Pirate Roberts nickname posted a defiant message on the Silk Road forum.
"It took the FBI two-and-a-half years to do what they did ... but four weeks of temporary silence is all they got," they wrote.
(Read more: Bitcoin is back: Online currency gaining traction)
A Twitter account for the administrator has also been launched in conjunction with the website.
"You can never kill the idea of Silk Road," read the Twitter feed of the new Dread Pirate Roberts twenty minutes before the site's official launch.
Like the original Silk Road, users access the new site using an anti-surveillance service known as the Tor network instead of traditional web browsers.
Ulbricht's lawyers said on Wednesday that the mastermind behind the original Silk Road will plead not guilty to drug trafficking, hacking and money laundering charges.
Court papers say the original Silk Road website generated sales of more than 9.5 million bitcoins, roughly equivalent to $1.2 billion.
Experts of the "dark web" said that the relaunched site could be as popular as its predecessor.
(Read more: Bitcoins worth $28 million seized from 'Silk Road owner')
"The popularity of Silk Road -- which to a great extent made bitcoin as popular as it has now become -- was meeting a need. Just because Silk Road closed down it doesn't mean the demand will go down," Professor Tim Watson, director of the Cyber Security Centre at De Montfort University, told CNBC.
But he said that now Silk Road is well-known to law enforcement authorities, it could impact trust in the new website.
The bitcoin price saw a sharp surge today rising above $300, but Watson said that it is difficult to attribute this just to the Silk Road news.
The original Silk Road is not the only anonymous black market site to have been shut down recently. Atlantis, which also sold illegal drugs, announced it was shutting down for "security" reasons, allowing users to take their bitcoins one week before it went offline.
Another similar site called Project Black Flag was closed by the administrator who said he or she had "panicked" and stolen the site's bitcoins.
—By CNBC's Arjun Kharpal: Follow him on Twitter @ArjunKharpal