I've also had a similar problem, I have visited this site twice in the past few days and both times I'm unexpectedly directed to a page that claims to be searching my computer for virus'
I've seen this before on other websites, it's a scam to try and get people to download fake anti-virus protection, I'm just concerned because I wouldn't expect it to come from a site like this unless someone has hacked into the site somehow.
It seems to be on a timer because I can't recreate it, it gets me when I don't expect it but I will get a screenshot if I can next time it happens,