Organised syndicates are dominating illegal activity on the Dark Web in a market worth £26 million, according to new research.

The marketplace Agora apparently hosts 1233 sellers spread across 20 countries, undercover researchers from the University of East London (UEL) discovered during an investigation. There were 30,000 products on sale.

However, 90 percent of the market was run by 10 percent of sellers, which the UEL team called a “criminal oligarchy”.

Products for sale included ID documents such as passports and driving licenses, drugs and weapons.

Agora was found to be dominated by drug dealing, with 80 percent of the market share going to the selling and purchase of drugs.

“Big players offering huge amounts of drugs strongly suggests we’re dealing with large organised gangs,” said Dr Andreas Baravalle, senior lecturer in computing at UEL. “They’re using the Dark Web to trade in drugs on a global scale, thanks to the anonymised world of the Dark Web and new virtual currencies like Bitcoin.”

The team drew this conclusion partially due to the large bulk quantities of drugs that were being sold. With hashish, the mean amount on sale was 47g, with a median of 10g, but with some sellers selling up to 1 kg at the time.

According to the report, a seller called RADICALRX was offering a cache of £10 million pounds worth of drugs. These included Hydromorphone, Oxycodone, Fentanyl and Meth.

Germany and the USA had the largest markets in drug sales, while the USA, Australia and the UK had the largest number of individual vendors.

“This is hardly teenagers in basements – the scale is the one of organised crime,” said the report.

In the illegal documents category, the team found 84 scans and photos of passports on sale, with 12 physical passports.

A physical UK passport was on sale from £752 and scanned passports could be purchased for £7.

To conduct its research, the team had to evade detection by the administrators of the website, who used a range of techniques to try and sniff out potential spies.

A total of 30,680 records were collected during the study between 22 July 2015 and 3 September 2015. The site was shut down in September 2015.