ORANGE COUNTY -- Pet owners in Mauriceville are heart-broken after family dogs started turning up dead. The mysterious deaths started Wednesday morning.

Homeowners in the Greenwood Acres subdivision tell 12 News that 18 dogs have died. The Orange County Sheriff's Office has confirmed 8 deaths; saying some pet owners haven't contacted authorities.

All of the dogs that died are believed to have ingested strychnine which is a poison used to kill rodents.

"Why do something like this to them? They're innocent. They can't defend themselves," says pet owner Robert Johnson.

Johnson owns a dog named "Toby", a miniature schnauzer who also ingested the poison.

Toby has been the only survivor.

"They rushed him in and we were able to get treatment. We started right away," says Veterinarian Blake Foskey with Foskey Veterinary Clinic.

While doctors worked to save Toby, Johnson spent the night wondering if he'd pull through.

A tearful Johnson cried out, "I had no idea whether I was going to see him again."

Blake Foskey says dogs affected are seeing similar signs of poisoning, all very painful to the dogs.

"They're having violent seizures, usually without previous signs. They just lock up, their legs stiffen, they fall over, begin breathing heavily and panting," he says.

While 12 News was talking to pet owners, other neighbors on the lookout for what looked to be poison along the road. It was given to sheriff's deputies to send off for testing.

While deputies investigate, pet owners are hoping their four-legged family members are left alone.

"A lot of people will look and say 'It's just a dog'. They're more than that. He's (Toby) more than that," says Johnson.

Anyone who sees suspicious activity, or knows who may be responsible for this animal cruelty case, is asked to contact the Orange County Sheriff's Office at 409-883-2612.