Pet owners are crying foul after an accident at the Mainland Common in Halifax forced one owner to euthanize his dog.

Mike Goneau's Saturday morning routine with his dog Bear turned tragic this week. The pair was visiting the Mainland Common dog park, and as Bear was playing in this grassy area he fell into a sinkhole.

“I heard a scream and a wail and a cry that I'd never heard from an animal before,” says Goneau.

The 10-and-a-half-year-old dog broke his shoulder. The vet determined the best course of action was to have Bear euthanized.

The sinkhole is large enough for a person to get into, but hidden by tall grass. The entire area is filled with depressions and holes.

Dog owner George Hickey says it's been that way for months, and has already addressed the issue with two area councillors.

“It's an HRM park so it's their responsibility to ensure there's a standard of safety that's adhered to for the users of the park,” Hickey says. “A dog or a person was bound to fall into one of those holes and get hurt.”

Halifax Regional Municipality staff say there were no open files about the park before Monday, meaning anything that was reported to 311 before this weekend was considered closed.

Municipal officials say sinkholes in this area have been filled in before, but the permanent solution is not as simple as just filling in the holes with some dirt.

“When there's rain it will just wash away, so we need to put sandstone or gravel,” says Brendan Elliott, spokesperson for the Halifax Regional Municipality.

Contractors began installing a temporary fence to the problem area Monday afternoon. The holes will be marked until a permanent fix is in place, but officials admit they're not sure why that didn't happen before.

The municipality is also considering having staff monitor the park on a weekly basis.

Goneau says he's happy changes are being made, but he's angry his dog had to die to make it happen.

“I want every dog that does come here to play here and be safe.”

With files from CTV Atlantic’s Sarah Ritchie.