UPDATE: I’ve received a response from Facebook, who says that “unfortunately, this was indeed a glitch in our spam prevention system.”

We integrate with many different external blacklists including Norton and when there’s a block on their service we provide a warning to our users. We only use our external blacklist system to protect our users and would never use it to reduce traffic for competitive reasons.

ORIGINAL ARTICLE: Is Facebook purposefully scaring users with questionable security alerts in order to cut traffic to Google+?

That’s the story coming from some Google+ users. They claim that when clicked, certain links to Google+ that appear on Facebook are displaying a frightening warning message to its users – “Security Alert: This Link May Not Be Safe.”

And the warning comes courtesy of Symantec.

Elgan Media’s Mike Elgan shared this to Google+ early this morning:

Mike Elgan 10 hours ago

Facebook resorting to ever more dirty tricks against Google+.

Facebook has taken its cheating to a new low. 

As you know, I auto-post Google+ posts to Facebook. The link brings my Facebook followers back to Google+ for the pictures and comments and for the complete post. 

But now, when they click on the link, my followers get a scary "Security Alert: This Link May Not Be Safe" warning.  

As far as I can tell, Facebook is lying. Flat-out lying as a dirty trick to reduce traffic to Google+. I can't think of any other explanation. 

And they're apparently paying Symantec to take the blame for the lie. 

Both companies know that a link to Google+ is perfectly safe. There are no banner ads and no way for malicious code to be downloaded from Google+. There has never, to the best of my knowledge, been a malware event originating from a Google+ link. 

Even after you click "Ignore this warning," every single link is flagged in the same way, with no "learning" or option to accept all links from the site. 

I wonder what +Robert Scoble thinks of this.

Props to +Roberto Acevedo III for pointing this out to me.  1773    500 Powered by socialditto

A few hours later, Elgan posted an update that said “Facebook is no longer putting up a ‘Security Alert’ for Google+ links. I guess they didn’t like the bad publicity. Let’s hear it for the power of the ‘What’s Hot’ list!!”

Some commenters continued to report that they were still getting the message, albeit with the stuff from Norton removed.

I don’t get a Norton warning, but I get a security alert. I guess Norton busted Facebooks balls for exploiting their name, and now they changed it to the following:

“Please be careful
For the safety and privacy of your Facebook account, remember to never enter your password unless you’re on the real Facebook web site. Also be sure to only download software from sites you trust. To learn more about staying safe on the internet, visit Facebook’s Security Page. Please also read the Wikipedia articles on malware and phishing.”

Others said that the problem is hardly new:

Bubble bursting… this has been happening for many many months… the alerts for some people will show and then stop…. you are not special +Mike Elgan I have posted about this a few times (with screenshots) over the last few months.

As far as I can tell it is triggered when there is a certain amount and kind of activity along with content topics… gasp! Yes, topics… FB does censor! OMG! What a thought! No, it cannot be! Anyway…. this is LAME that this is on whats hot as it has, as I stated, been happening on and off since the early days of G+… Many others have posted about it as well many times over the past year of G+’s life.

In April, Facebook announced a deal with a few security companies – Symantec’s Norton Antivirus being one of them. The deal now allows users to download free trial periods of their software, and it also gave Facebook access to their data on malicious sites.

FYI, if you run Norton’s Safe Web Check on Google+, it comes up clean.

I’ve reached out to Facebook for comment and will update this article accordingly.