I've been scanning a lot of photos recently, more than one at a time. I now have multiple jpegs, each containing multiple photos.

Can I, using Gimp, "split" a jpg into 3 smaller files ?

What I used to do is : copy the jpg 3 times, and crop a different picture in each copy.

There must be an easier way to do this !

EDIT : Is there a plugin that can do that ? I've looked around, but only found plugins that "cut" an image into pieces of equal size.