Boris Johnson's personal mobile phone number available online for 15 years

Boris Johnson's personal mobile phone number has been freely available on the internet for the past 15 years, it has been revealed.
It was published in a think tank press release in 2006, but never deleted - and appears to be the one the PM uses.
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Former national security adviser Lord Ricketts warned hostile states with "sophisticated cyber capabilities" or criminal gangs could now have access to Mr Johnson's digits.
Sounds like anyone with Google has access to it, with or without sophisticated capabilities.