Lost iPhone, should I erase it?

My iPhone was stolen & I used find my iPhone to see that it has been tracked to a pretty seedy apartment complex. The thief turned the phone off (or it died) & now I'm not even sure that it's still there. So I'm using my old 3 right now but after I backed it up I found that none of my photos were there. About 3 months of pictures. So should I wipe the phone? Is there a way to get the photos from iCloud? If I wipe the phone would it delete the photos from iCloud?
Thank you

No, it won't delete the photos only if you backed it up with iCloud, you can even stream it to your computer. So it is safe for you to delete it, but if I were you, I would set a passlock. That way they can only use the iPhone if they restore it, and they won't because to restore it, they need to remove the passlock.