One of the largest dark web drug marketplaces is closing down in a surprisingly professional manner

When deep web drug markets go offline, the fallout tends to be explosive. It could be a high-profile police raid sowing fear throughout the community, or a sudden disappearance that has short-changed drug dealers and customers calling scam. Not so with Agora.

One of the largest drug marketplaces around, Agora announced Tuesday evening that it was to "pause operations" due to security concerns, and is calling upon its users to finish up transactions in a timely manner before it closes down.

Agora - and the dozens of other dark web markets out there - act as a kind of black-market eBay. Vendors can sell drugs and other contraband through the site, and are left reviews by customers. The sites' administrators skim off a percentage fee, and are on hand to help handle any disputes. Because of the flagrantly illegal nature of the content sold, payments are typically made in digital currency bitcoin to ensure anonymity, while the sites themselves are only accessible through web browsers configured to use Tor, an anonymising network.

The first major dark web market on the scene was Silk Road. Launched in early 2011, it became the subject of significant media attention before it was shuttered by the FBI in 2013. Ross Ulbricht, a 31-year-old Texan, was subsequently convicted of operating the site, and sentenced to decades behind bars - but this didn't stop the deep web drug trade.

Since Ulbricht's arrest, the number of marketplaces have shot up. Just a month after the first Silk Road's closure, Silk Road 2.0 sprung up, led by a group of administrators from the original. A year to the day after it was launched, it too was closed in a police raid, and alleged operator Blake Benthall is now awaiting trial.

Not all deep web markets close in arrests; some simply vanish in what appear to be scams. Evolution is the highest-profile example of this. After Silk Road 2.0 closed down, it grew to become the largest market on the scene - before abruptly closing down in March 2015, apparently with more than $12 million of bitcoin. The dark web community widely believes this was a deliberate exit scam to defraud users.

In contrast, Agora's decision to temporarily halt operations has been remarkably professional. Citing "vulnerabilities in Tor Hidden Services protocol which could help to deanonymize server locations," a spokesperson wrote on Reddit community r/DarkNetMarkets that "while we don't have a solution ready it would be unsafe to keep our users using the service, since they would be in jeopardy." So, they continue, "to our great sadness we have to take the market offline for a while, until we can develop a better solution. This is the best course of action for everyone involved."

Agora isn't offline yet. It will likely go down in the coming days. Meanwhile, it says it is "[doing] our best to clear all outstanding orders," and it also "[asks] all of you users who have money on their accounts, withdraw them as soon as possible, because we don't want to be responsible for it during the time when the market will be offline."

The announcement has drawn immediate praise from the community. "Well, guess this is what I call a professional approach to business," wrote the most popular reply. "I'm amazed the guys were honest til the end," wrote another, "thank you for the amazing service Agora." Another offers "kudos for being as transparent as they can be."

There is no indication of how long Agora will be offline for.