Police in Thornbury believe someone is trying to harm pets at a local park.

Anne O'Hara is keeping a closer eye on her golden retriever Biggins these days, watching his every move and everything he sniffs out. This is after learning meat filled with nails was found at nearby Moreau Park.

“It’s ridiculous, terrible,” she says. “We've never had any problems with dogs and people complaining about them.”

A parent playing with their young child discovered several pieces of chicken spiked with small finishing nails scattered in the area next to a playground and an off-leash dog area. The park is a popular area for dog owners and many here can't imagine why anyone would do this.

“Any problem like this in a public area is just a sick side of society and can't be condoned,” says John Corrigan.

Claire Brooks adds, “If they see a piece of meat that's there they will go after it right away and we might not be able to get it in time. So it’s awful, I’m disgusted.”

OPP believe they have collected all of the meat and say there weren’t any injuries to people or pets. But police don't know who is responsible or what their motive was.

“It certainly is concerning that this was deliberately placed here by someone who wanted to harm someone’s pet or child,” says OPP Const. Martin Hachey.

Doctor Nicola Haessler has been a veterinarian in the Blue Mountains for a decade and has never heard or seen anything like this before. She says the nails are small enough for a dog to pass if consumed but the internal damage can be deadly.

“It would be pretty easy for these nails to perforate the intestines and stomach and that could lead to an infection that could be life threatening,” she says.

Haessler says pet owners should keep a close eye on their dogs for any unusual behaviour or vomiting. As for pet owners, many say they will continue to bring their dogs to the park but will be extra cautious.

Police are warning parents and pet owners to be careful when at the park and to keep their pets on leashes. If you find anything suspicious, police say to bag it and report it immediately.