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MONTGOMERY COUNTY, Texas - Four of the stray dogs were well-known to residents who would feed them.
"Almost like family. Because you love dogs, almost as much as you love human beings," said Linda Stephens.
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Stephens had been feeding four dogs regularly, and they spent a lot of time hanging around her yard on Auction Barn Road in Cleveland.
"The brown and cream dog wasn't eating, so I came down the steps, and he was foaming at the mouth," Stephens said. "Then I walk a little farther to the driveway and I see the black dog under my truck, and he was foaming from the mouth."
Another deceased dog, who just had puppies, was found under Stephens' house.
"I think there's a monster walking around here poisoning dogs," said street dog rescuer and feeder, Brat Hilton.
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Hilton says other dogs in the area have mysteriously died.
"The neighbors across the street already had two of their dogs poisoned a few weeks ago, one actually survived," Hilton said. "The other neighbor has one dead in her yard. She didn't know whose dog it was, but it was laying there dead."
Residents say they tried for three days to get law enforcement involved, and the dead dogs picked up.
"We had the ones right here that people were passing by, and you could smell what he was going under to pull out, so I knew it was coming," said dog rescuer Katie Logerot. "It was bad. You could obviously tell she was nursing, and she had babies."
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Nine newborn puppies were found nursing on their dead mama.
"Two of them were trying hard to nurse on her, and it was horrible, heartbreaking to see that," Hilton said.
On Wednesday, the Montgomery County Precinct 2 Constables Office began an investigation.
Montgomery County Animal Control collected the carcasses.
"The problem out here in Cleveland, it's ridiculous," said street dog feeder, Nikki Kerr. "There's so many stray dogs, and it doesn't seem like anybody cares."
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"I'm up all through the night since this happened. I can't sleep," Stephens said.
"They didn't deserve that. They were very friendly dogs, so there was no reason," said street dog feeder, Faith Washechek.
"They had a horrible death at the end," Hilton said.