Have been hijacked by macsecurity-alert.com. MY husband's mac mini is using 10.9.5. When trying to log on to safari, he is stuck with a "System Alert". I have tried the force quit and can do that, but holding the shift key while trying to open Safari does not get me anywhere. I turned off the wi fi and the connection to the internet. Tried a restart and the page STILL loads with the bogus www. address and the pop up. I have even played control R with the reload page trick and cannot get any thing to work. All Safari menu options are grayed out.

Short of having a huge freakout, what should I try next?
THANK YOU!!!

Have you seen A Browser Pop-up has Taken Over Safari? Scroll down to "none of this worked" for more ideas.

often a force quit is the only reasonable way out. but then safari likes to reopen pages when relaunched. turning off javascript seems to be the best way to deal with them sometimes.

I looked at scam zapper, hoping it was something that would detect the lock-in windows themselves, but that doesn't look like what it's doing. It appears to have a blacklist of known URLs that host them, and so it only works for sites in its list. That's not nearly as useful.