I have about 7k files which are all photos imported in my PC ( Windows 7 ), however when it was finished importing an error came up, and I had to cancel the "Delete files from device after importing"part and I had to replug my iPhone. SO, my problem is I have to delete those photos (which are 7K) on my iPhone, and I couldn't find the option in PC to remove those files on my iPhone even though it recognizes that those pictures were already imported.

Do I need to delete the imported files then import it again to continue the deleting part??? [honestly, 7k files take forever to import, and there's still more waiting]
Or there's another way to do it?

THANKS!

reply ASAP [cause I need space]