At least five dogs have died and several more are sick after visiting popular beaches on the Sunshine Coast, prompting serious warnings from vets.
Local dog owners were put on alert on Tuesday after a series of pets presented to a local veterinary clinic with concerning symptoms.
North Coast Veterinary Emergency and Critical Care said the dogs were coming into the clinic with symptoms that suggested they all ingested something toxic.
"Although we are unable to confirm the cause of these presentations the link to these patients is the area that they have walked within the 12 hours prior," the clinic said on a Facebook post.
The post also warned against walking pets around the beach areas of Buddina, Kawana, Point Cartwright and La Balsa.
Sunshine Coast Council confirmed to ABC News that five dogs had to be put down after experiencing symptoms of poisoning.
Heartbroken owners share devastating stories online
One man said his six-month-old puppy became ill last Wednesday after a trip to Kawana Beach and eventually he had to make the heartbreaking decision to put her down on Saturday.
He urged people to stay from the area, saying there had been several dogs who died within hours of going there, and even more who were seriously ill but survived.
The beaches are all part of one continuous coastline, with the affected areas appearing along a two kilometre stretch.
"This doesn’t seem like a coincidence so I’d recommend steering clear for now," he said.
"Please share around as I don’t want any other beloved pets to die or anyone else to go through what I have. Absolutely heartbroken."
A pet rescue said on Facebook a beautiful dog named Sophie, who was on an adoption trial, died over the weekend.
One of the workers at the rescue facility said it is believed Sophie fell victim to the mysterious illness stemming from the beaches.
Sophie's new owner and her foster mum are distraught by her death.
Another post made by Doggie Adventure Playhouse claimed a dog named Billy may also be a victim of the potential poisoning.
"Unfortunately our darling Billy was walking at Buddina on Sunday and passed away in the early hours of Monday morning," the post read.
There have been theories foul play is involved, however the cause of the deaths is yet to be confirmed.
"How anyone could be that cold and evil as to intentionally set about to kill dogs and cause the heartbreak to the family," the post said.
"Dogs are our hearts, our love, our companions and faithful cuddle buddies."
Symptoms pet owners need to be aware of
A screenshot of a message – which was apparently sent by a vet – has gone viral on social media.
The message claims there had been five deaths in 72 hours after the animals went to the beach.
"I don't know if they're all connected or not. But too coincidental not to take seriously," the message says.
North Coast Veterinary Emergency and Critical Care urged dog owners to be on the look out for gastrointestinal upsets, lethargy, or any changes to the dog's behaviour.
"We have chosen to err on the side of caution and have made local authorities aware," the clinic said.
"Please do not hesitate to reach out to us or your local veterinarian if you have concerns."
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