When you turn ON "Auto Sync" feature for Flickr on iPhone and the uploaded photos will store in "Auto Sync" album. The "Auto Sync" album is automatically generated by the Flickr app on your iPhone. Normally you can delete an album from Flickr, but you can delete "Auto Sync" album from Flickr as there is no "Delete album" option. You have one option i.e open "Flickr app on your iPhone and go to "Auto Sync" album and then select "Edit". Tap on all photos and then click "Trash" icon.
Quick Tip to ensure your Photos never go missing
Photos are precious memories and all of us never want to ever lose them to hard disk crashes or missing drives. PicBackMan is the easiest and simplest way to keep your photos safely backed up in one or more online accounts. Simply download PicBackMan (it's free!), register your account, connect to your online store and tell PicBackMan where your photos are - PicBackMan does the rest, automatically. It bulk uploads all photos and keeps looking for new ones and uploads those too. You don't have to ever touch it.