>... and more serious organised crime, were our security services not using the bulk surveillance data ...

In the unlikely case these aren't pranks, they would almost certainly be GCHQ astroturfing accounts. Of course, the astroturfing itself is of so poor quality that they probably outsourced the job to either some apathetic social media/perception management firm, or clueless interns.

I could easily see a social engagement platform that's primarily used to spam Disqus comment sections also having support for HN, just for the sake of ticking the box.