Who, Why, Where, When and What the HEK?

One fascinating thing about REALNEO is the interconnection it enables - in July 2007 I posted an article about some tagging in my new neighborhood of the time [1], at W. 45th and Detroit, by HEK. Since then, HEK tags have spread to every corner of the community, and I've never seen an explanation Who, Why, Where, When and What the HEK? Well, today I received an email from a stranger who found my posting through a Google search and has some very personal concerns about HEK, beyond vandalism.

The stranger asked for anonymity and confidentiality so I won't share any details of the message I received, other than it indicates HEK is a person they know, and dangerous, and wonders if there is a connection with a large organized crime gang like the Hell's Angels. I've asked a few people in various HEK-tagged neighborhoods, who know the inner workings and gangs of their neighborhoods, and I haven't found anyone else who knows anything about HEK.

Anyone out there have a clue? HEK, want to speak up here?