JQuery :: Using Livequery With Fancybox On Dynamically Loaded Images

I have a page that contains images, and those images are displayed in a fancybox window when they are clicked. Some of these images are loaded dynamically after the page loads via AJAX.

All of the images exist inside of link tags with class="challenge_image_gallery". The code works the way it should on the images that are initially loaded on the page. However, when the new images are loaded onto the page using AJAX, the fancybox window loads two instances of the image that was clicked on rather than one as it should.

Here's the code I'm using: