I'll post a trip report later this week, but wanted to share this now in case anyone knows anything about it or can offer advice about reporting it to the rangers...

On evening of 8/30, my group set up camp at Lone Pine Lake. After dark, a group of 4-6 brawny guys arrived and set up their tents. Nothing unusual except in the morning I noticed they were about 50 feet from the water.

Mid/late morning, I saw smoke coming from their site. They had created a campfire by burning the end of a fallen tree that was propped up on another tree. I walked over and the conversation went like this...

Me: hey you guys know fires are illegal here?
guy: no they're not (staring me down)
Me: there's a sign right there that says "no fires"
guy: we're below that sign
other guy: thanks for letting us know (also staring me down)

Well, I'm not going to fight 6 huge dudes in the wilderness, so I backed off.
Then, half an hour later several gunshots went off and I saw a couple of the guys ducking behind a boulder, then silence. One of the guys later told my dad (on our way out) that he left his 9mil ammunition too close to the fire and it was exploding; the guy said he "would report it later"

They had said they were going up to Trail Camp next, but I didn't see them again. My dad filled out a report form of some kind at the Interagency Visitors Center, but I want to follow up if it would be helpful. Any suggestions about reporting it?
Thanks