British authorities knew about US plans to arrest Marcus Hutchins

GCHQ allowed Hutchins to fly and be arrested to avoid extradition battle

Leaders at intelligence and security organisation GCHQ were aware that the FBI was watching Marcus Hutchins - the security researcher who helped to stop the spread of the WannaCry ransomware earlier this year - before he flew to the USA, and was subsequently arrested, in July.

The Sunday Times reports that GCHQ was aware that Hutchins was under investigation by the FBI for his role in creating the Kronos banking trojan in 2014, before he flew.

A source said that the arrest, on the 2nd August, meant that the British government did not have to deal with the "headache of an extradition battle" with its ally.

Hutchins, who tweets as @MalwareTechBlog, is said to have helped to create the little-known banking trojan three years ago. Access was sold for $7,000 at a time, and the software focused on stealing banking credentials from compromised computers. The form-grabbing and HTML content injection element of Kronos was spread via phishing emails.

Kronos also offered modules for evading detection and analysis, and buyers were even given an option to trial it for a week for $1,000.

Hutchins pleaded not guilty in the case, brought to court in Milwaukee after being released on bail from custody in Las Vegas, but has admitted to writing part of the malware in question. He now faces six charges and up to 40 years in prison.

A source told The Sunday Times, "Our US partners aren't impressed that some people who they believe to have cases against [them] for computer-related offences have managed to avoid extradition. Hutchins's arrest freed the British government and intelligence agencies from yet another headache of an extradition battle."

Hutchins, as can be seen from his Twitter, is currently living in LA while he awaits trial.