Getting Unwanted Fake Followers On Instagram?

[Adam]

Recently I have noticed that I am getting lots of fake followers on Instagram . They all have their description set as the same name twice (Ex. Analisa Analisa) and have a picture of a site called EliteGram. I have never even heard of elitegram until now, nor have I gone on that site to get fake followers. I have a page with 15k followers, which up until now were all real and active ones. I would really like this to stop as I want to know how many true followers I have. Has anyone else had this problem or know how to fix it? And is it possible to mass block people (so that they aren't my follower anymore). Here is a picture: http://i42.tinypic.com/6jkj1l.jpg