Police have arrested a man after he allegedly sexually assaulted multiple ponies in Delaware.

Michael Riego was apprehended on Thursday at the New Castle County Carousel Park and Equestrian Center. Police were watching the center’s stables as part of an open investigation when they saw the 31-year-old peering into a pony’s stall, CBS affiliate KYW-TV reports.

Police say that Riego went into the stall and bound the pony’s rear legs. He was hiding in the corner when officers entered the stables to arrest him.

An investigation into the matter had been ongoing since February, following numerous reports of injured ponies at the center’s stables. The ponies were found to be wounded and their legs tied with cords just above the hoof.

Of the ponies involved, one was a 17-year-old black and white mare who had difficulty walking after her rear legs were injured. In another incident from last September, a 20-year-old mare had a cord wrapped around one of her rear legs. Surveillance footage showed a white man in a dark jacket going into the stables after midnight on each night. Police established that the same man was connected to both incidents.

Another report surfaced on April 20, this time involving a 31-year-old brown mare. Footage showed Riego picking up the barn’s feed bucket, going into the stall, tying the pony’s legs, removing pieces of clothing, and then sexually assaulting the pony. Police couldn’t identify Riego in prior incidents because he covered his face.

Police say that all the ponies have recovered. Riego, meanwhile, is facing felony bestiality and burglary charges. It’s predicted that he will be hit with more charges as the investigation continues.

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