The City of Toronto is warning residents to keep their dogs on-leash at Woodbine Park after Toronto Animal Services removed 30 ducks and one heron found dead in the area.

The deceased animals were found near an off-leash area this weekend. City officials said some dogs were seen in the vicinity of the ducks at the time.

Toronto Animal Services said all of the dead animals have been taken for further investigation to determine a cause.

Meanwhile, in a news release issued on Monday the city said they are urging dog owners to keep their pets on-leash in the area.

“All dog owners should ensure that dogs are leashed in Woodbine Park, including in the off-leash area, until the cause of death has been determined,” the news release said.

Speaking with CP24 on Monday, a local dog owner Catherine Bray said she will be taking extra precaution with her two dogs after hearing this information.

“This is very strange,” she said. “I’ve lived here all my life and we’ve certainly never seen anything like this before. We see ducks and heron down here all the time when we’re walking but never anything like that. It’s generally a very safe area for kids, dogs and all animals.”

The city is also urging dog owners to contact their veterinarian if their dog was at Woodbine Park on Sunday and is experience any signs of illness.