There seems to be some turbulence going on in the murky world of the dark web, with four of its major drug marketplaces unexpectedly going offline, reports said.

The dark web is a section of the internet where people contact each other anonymously without the fear of being monitored. It is usually used by criminals to sell drugs, chemicals, weapons, child abuse images and even offer assassination services.

Websites The Trade Route, Tochka, Wall Street Market and Dream Market, were down without any notification or clarification from the sites’ administrators.

According to some users of such markets, this might either be a DDoS attack by a hacker or a large scale action by law enforcement authorities.

However, there are more chances of the former happening than the latter. Some dark web users have also started complaining of botnet attacks.

Another farfetched theory is that this is scam by a bunch of drug dealers — taking off with the money of their clients while not providing them with the required merchandize.

With no notification or clarification from the sites’ administrators, the exact reason for the sudden disappearance of such marketplaces remains unclear.

However, a user going by the name Automoderator commented on a the subreddit /r/DarkNetMarketNoobs that the WallStreetMarket is not listed currently, as it is facing “very serious issues” and warned others to avoid it all costs. Some other users on the subreddit say that the Dream Market has been working fine on all its mirrors, but, however its main site is down.

At the time of writing, the marketplaces were still down, according to dark web marketplace tracker deepdotweb.

Many sites on the dark web are also run by law enforcement — the Australian Police ran one of the world’s biggest child porn sites on the dark web between October 2016 and September 2017, called Child’s Play, in an effort to nab pedophiles.

The police grabbed the administrator access from two cyber criminals — Benjamin Faulkner and Patrick Falte and started administering the sites. Police even posted more child porn on the site in an effort to convince the viewers that the site had not been taken over by the authorities.

By the time they shut down the site, police were able to nab more than 90 pedophiles in Australia and 900 across the world. In case, the marketplaces were being taken over by law enforcement to nab drug traffickers and child porn purveyors, it might be a different case.

However the development has many dark web users in a state of paranoia and many users have posted on Reddit reminding other users of such busts. Such attacks on dark web markets in the past have usually begun with large-scale DDoS attacks.

In July, a massive trans-continental sting saw two of the dark web’s biggest sites at the time, AlphaBay and Hansa, being taken down.

Law enforcement agencies claimed they were able to collect incriminating information on hundreds of buyers and vendors, going as far as threatening to prosecute them.