Paris, so sorry you witnessed this and then didn't know who to call. So whatever town you are in would determine which police dept you would call. Any officer could investigate it, it wouldn't have to be an animal control officer. I hope too that the dog is ok. Thank you for wanting to help. Again, where ever the crime occurred is the law enforcement agency that would handle it.
Call your local authorities also. If he is currently traveling in California then he is bound by your local laws.
Animal cruelty is definitely against the law, but the authorities that would prosecute him would depend on where he lives. If you have documented proof (picture/video) I'd submit that to a police department in Utah. Salt Lake is big and gets a lot of calls and such, but you could definitely call the Spanish Fork police department and report it. Hopefully they'll be able to find the guy and save the poor dog.
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