Someone has dumped at least a dozen sickly small-breed dogs outside a Detroit PetSmart since April.

After chasing down four dogs around the store this week, pet store employees have a message for the person abandoning the canines.

"If they'd just call us, we can refer them to a rescue group or the Humane Society; we just don't want this continuing," store manager Nikki Taylor told the Detroit Free Press.

Most of the dogs have been left next to the trash bin behind the store, but some have been dumped in the parking lot or at nearby businesses.

The dogs range in age from 2 years to 6 years old, and each weighs about 10 to 15 pounds. They’re likely from the same poodle-Maltese breeding line, according to Theresa Cetnarowski, a volunteer with the Animal Welfare Society of Southeastern Michigan, which is caring for the dogs.

All of the animals are underweight and have filthy, matted fur.

"They're in terrible condition — completely matted, full of feces, nails never trimmed, just skin and bones," Cetnarowski said.

PetSmart employees contacted police about the matter, but were told they needed an eyewitness who can report the dumping or provide a license plate number for the vehicle.

"I think it's a breeding situation. I guess they have too many and they're overwhelmed. Or it could also be a hoarding situation. But whatever's going on, it's pretty heartless that they're dropping them off by the freeway," said Ashley LaPorte, an animal care specialist at the rescue organization.

The Animal Welfare Society of Southeastern Michigan will put the dumped dogs up for adoption once they’re healthy. The rescue group is accepting donations to help care for the dogs.

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Laura Moss writes about a variety of topics with a focus on animals, science, language and culture. But she mostly writes about cats.

Detroit seeks mystery dog dumper
Since April, a number of underweight dogs with matted fur have been abandoned outside a pet store.