Advertisement on facebook group chats?

[Natascha]

For the last couple of weeks i keep getting invited into these group chats on facebook when somebody has left a message saying 'omg just picked up a new iPad for 15 quid from this site!! http://t.co/4zgJGBeHpb' and for some reason i have started one. I dont have any relation with this wippy site and i dont know how they know my Facebook. But could someone just tell me if i can stop this and if so how thanks

[kyle]

This is interesting that you are having this issue!
I have been having the same issue as well for a couple of weeks, but I was able to quickly reverse the damage. Now, about two months ago there was one that was going around claiming that you could lose tons of weight with a method seen on the Dr. Oz show, and it was a phishing site that accesses your password, and sends posts about it to wherever it can go.
These people that do this are very intelligent, and they can bypass all of your security features.
So, based on what you are saying, that is a malicious link that does access your account and based upon a code, it automatically sends messages to as many people as it can. It is all a method for them to get traffic. The easy way to get rid of this would be for people to report that link as spammy or unsafe, or you can also contact the facebook developers, if you believe that it is becoming increasingly difficult to deal with. Facebook stives to keep a safe environment for it's over 1 billion users, but it gets trickier when there is criminals behind keyboards.
Never click on one of these links.