Updated

Marcus Hutchins, a young British researcher credited with derailing a global cyberattack in May, has been arrested for allegedly creating and distributing banking malware, U.S. authorities say.

Hutchins was detained in Las Vegas on his way back to Britain from an annual gathering of hackers and IT security gurus. A grand jury indictment charges Hutchins with "creating and distributing" malware known as the Kronos banking Trojan.

Such malware infects web browsers, then captures usernames and passwords when an unsuspecting user visits a bank or other trusted location.

The news was first reported by tech publication Motherboard. It came as a shock to a cybersecurity community which had rallied behind Hutchins, whose quick thinking helped control the spread of the WannaCry attack that crippled thousands of computers last May.