The U.S. Department of Justice, along with a number of additional law enforcement agencies, Thursday helped take down Silk Road 2.0 and a number of other “Dark Web” or “Dark Market” websites used for selling illegal goods and services.

The websites targeted in the bust are used to sell range of illegal goods and services for sale on the “Tor” network, which is “a special network of computers on the Internet designed to conceal the true IP addresses of the computers on the network,” according to an FBI release.

However, less than 24 hours after Silk Road 2.0 was shut down, a new website popped up.

According to the Los Angeles Times:

On Friday, an underground website calling itself Silk Road 3.0 Reloaded claimed to be open for business on the TOR network, which is linked globally through special browsers that encrypt Internet traffic. Several other websites on the TOR network also claimed to be open for drug transactions.

The dark Web poses new and formidable challenges for law enforcement agencies around the world that have been dealing for decades with more conventional international drug trafficking.