NARRAGANSETT, R.I. — An animal welfare organization is offering a $500 reward for information that leads to the arrest and conviction of the person who shot a dog in the head and left the body in a Narragansett river.

Narragansett police in a Facebook post Thursday said the black, terrier-type dog was found in the Narrow River late last month inside what appeared to be black garbage bags.

The male dog was 5 or 6 years old and had a skin infection “that would have been immediately recognizable to anyone who knew him," police said.

The Rhode Island Society for the Prevention of Cruelty to Animals is offering the reward.

“We would strongly encourage the owner or the person responsible for this act to come forward and identify themselves,” RISPCA President Joe Warzycha said in a statement. “We will continue to investigate this matter until all avenues are exhausted and any help from the general public would be greatly appreciated.”

Anyone with information is asked to either call police or the RISPCA.