Spam on Lighthouse

There's been an increasing amount of spam comments on tickets in the
Rails LH. Tender ticket is here:

I've been going through and *deleting* spam comments, as the "Mark As
Spam" button appears to simply hide the comment but leave active,
Google-followable links live on the page. Once a comment is marked as
spam, it doesn't appear to be possible to delete it...

Any thoughts on the best way to deal with this? I wish LH had a
"report this *user* as spam" button...

--Matt Jones

Well, I also wishing that they would have something like "Captcha" or human testing on the registration page. Right now it's a bit too easy to create spam account.