How to apply org-todo to multiple items

Consider an emacs org-mode file like this: ** item 1 ** item 2 ** item 3 ** item 4 Now I can apply org-todo to every item separately (bound to C-c C-t). But how can I apply it to every item in region at once? Just selecting the region and doing it doesnt't work, it just adds the TODO keyword to the item below the region.