Dark net drug sales on the rise in England
The number of people in England buying drugs on the dark net has more than doubled since 2014, the Global Drugs Survey has found.
The annual survey questioned 123,814 people from more than 30 countries
Its data showed that, the number of drug users in England buying products on the dark net has risen from 12.4% to nearly 28.6% since 2014.
England also had the third highest number of illegal drugs delivered to order - behind Scotland and Brazil.
There were no specific figures about Wales or Northern Ireland in the study.
The study's founder, Dr Adam Winstock, says people do not understand the risks involved in buying drugs online.
"If you've given your name, somebody knows you've bought illicit drugs," he said.
"And then there's a possibility that they will blackmail you."
The dark net is a network of untraceable online activity and hidden websites.
In addition to the illegality, an investigation by the BBC podcast The Next Episode found hundreds of people claiming to have been scammed or blackmailed by vendors while trying to obtain drugs on the dark net.
Leon is one of them.
"I got a very angry and threatening message saying, 'I've got your address' and threatening to either release it, show up there, or send something nasty. This was someone who was a crack and heroin seller.
"Obviously I don't have any consumer protections legally."
In recent months the National Crime Agency, the organisation tasked with policing the dark net in the UK, has helped shut down several large dark net marketplaces.
But there has been criticism that this approach actually leads to more people being blackmailed.
Caleb Daniels is a crypto-market expert and he said: "What we are seeing is a perfect storm.
"More users are going online whilst untested sites are popping up.
"This leaves users vulnerable to blackmail."
A National Crime Agency spokesperson said: "Tackling the cyber-crime threat is a priority.
"We have had lots of operational successes and have led a number of investigations into criminal activity on the dark web, which have resulted in individuals being convicted and facing lengthy prison sentences.
"We would encourage anyone who is a victim of crime to report it to the authorities."
Dark net expert Chris Monteiro said: "Drug dealing on the dark net is not a priority for the police.
"The police are limited in what they can do and ill-equipped to deal with issues on the dark net."