But Mr Shtylman acknowledged on a forum that he had recently carried out an upgrade of his systems and stored an unencrypted copy of the keys during the process, which the thief took advantage of.

BBC: Bitcoin

Rather, Keys tweeted a copy of a "final written warning" he said he received from Reuters in October, which admonished him for unprofessional behavior after he mocked a Google executive from a fake Twitter account.

WSJ: Social media editor in court on hacking charges