How to delete iPhone photos on a Mac?

I connected my iPhone to the USB of my Mac and I have gone on image capture and itunes and there's nowhere that I can delete the pictures off of my iphone on my Mac. It just gives options to import them. What do I do to delete them off of my iphone from my computer?

I use iPhoto to import the photos and video captured by my iPhone (and Canon point & shoot camera). I use Image Capture to control the scanner portion of a Canon multi-function printer.

At the end of the import process, iPhoto asks if you want to keep the photos that were just imported - or not.

Import them using iPhoto, it then asks you if you want to keep the photos once you've imported them.

If the pictures were taken with the phone then they could be deleted through Image Capture.
If not, then they were likely synced on through iTunes in which case you'd have to use that to clear them off.