Make an animated gif with Asp.Net C#

As you can read in the blogpost about access jpg’s through ftp with asp.net. I have explained there how I connected with FTP and retrieved images of the IP security camera. Now I have slightly modified the LINQ so that it downloads the latest 3 images and I would like to animate the transition between them. Now I know that I can use some fancy jQuery for image transitions, but I would like to merge the three images in a Gif.