How to delete many photos on iPhone 4S?

My friend is a real dick, and he was holding my phone for me while I was at practice and took 2000 photos of himself on my phone. Now I have a iPhone 4S and I use one of the iOS 6's. Is there any way I can delete all of these photos in one swoop? It really is annoying me to just go through the photos clicking them all. It's far too many.

Deleting Photos Imported by iTunes to the iPhone
Step 1
Plug the iPhone into your Mac or PC using the cable that came with the iPhone.

Step 2
Click the iPhone icon in the left panel of the iTunes window that opens.

Step 3
Click the "Photos" tab at the top of the iTunes window.

Step 4
Clear the checkbox for all the photos and albums that you don't want on your iPhone. This tab has a list of photo albums and folders available for synchronization to your iPhone. If a photo, album or folder has a marked checkbox next to it, iTunes will send the photos to your iPhone. Photos imported this way can't be deleted on the iPhone. The only way to remove them is by clearing the checkboxes in this tab.

Step 5
Click the "Sync" button to remove or add any photos depending on your changes in the "Photos" tab.

Deleting Photos Taken on Your iPhone
Step 1
Remove any photos you've already imported to your Mac or PC. During the import process, iTunes asks if you want to delete the photos from your iPhone. This is a quick way to remove a group of photos from your iPhone. If you've already imported a large group of photos from your iPhone, delete them from your computer to see this option again. On a Mac, delete them from iPhoto or the folder you've selected in iTunes. On a PC, delete them from the folder or application you imported them into.

Step 2
Delete the iPod Photo Cache. This is necessary so iTunes will ask if you want to import the photos again. If you've synced the photos to a folder, go to that folder and drag the iPod Photo Cache in that folder to the Trash or Recycle Bin. If you're syncing to iPhoto, go to your "Pictures" folder in Finder, press the "Control" key and click on the iPhoto Library, then click "Show Package Contents" in the menu that appears. Drag the iPod Photo Cache to the Trash.

Step 3
Plug the iPhone into your Mac or PC using the cable that came with the iPhone.

Step 4
Click the iPhone icon in the panel on the left side of iTunes.

Step 5
Click the "Sync" button, then click "Delete Originals" in the window that appears to delete the photos from the iPhone.

You can press the edit button on the top right corner and pick the 2000 photos of your friends and then press the red delete button at the bottom right corner and the pics are gone!