A massive hoard of fake Twitter accounts has been lying dormant since 2013. Several of these now-dormant accounts are used by their creators to fake follower numbers, send spam and boost interest in trending topics, researchers from London have discovered.

The trove of fake accounts, uncovered by two researchers from the University College London, Juan Echeverria Guzman and Shi Zhou, is tens of times larger than any public collection on Twitter bots discovered till date. In fact, the researchers say they are yet to come out with a detailed explanation and that the number of fake profiles may even be higher than estimates.

The researchers said these profiles were created in 2013 but have remained hidden. The dormant profiles are a great risk as the bot master who controls these accounts can wake them to spam and even spread fake news and tweets.

IBTimes UK spoke to Mark James, IT security specialist at ESET regarding this discovery, who said, "Social media is a very good platform to spread malware. Dodgy links, fake websites and generating likes for malicious reasons are all ways we have seen social media being used. Of course it's in Twitter's interest to keep the numbers legit but with hardware and software available today it's no surprise there are hundreds of thousands if not more fake or dummy accounts being used for the wrong reasons."

The researchers, who discovered the profiles, are now asking people to report similar bots to aid further investigation.