It sounds like they think humans did it.

An animal rights protection group is offering a €5,000 reward for information leading to the arrest of the person responsible for a vicious attack on a horse.
A horse was found dead in the Darndale Park area of Dublin with a number of injuries to its body yesterday. It was disemboweled and had its ears cut off and anus cut out.
Animal Rights Action Group (ARAN) has put up the reward to encourage those with any information on the crime to come forward.

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