It was a simple, seemingly innocuous act of disposal.

A woman in a white Jeep Wrangler drove up to a row of dumpsters outside an auto-parts store in Coachella, Calif., and hopped out with a plastic bag. She looked inside one bin but moved on, tossing her bag at the next dumpster, which already overflowed with refuse. On the grainy surveillance footage, it seemed that simple.

But it wasn’t everyday detritus inside that bag; instead, the bag was full of puppies — seven of them, all just days old, said investigators with the Riverside County Department of Animal Services.

And that’s what, authorities say, makes it so chilling.

The incident, which happened Thursday, set off a mad dash for information on the woman driving the white Jeep and led to a countrywide outpouring of support for the puppies, terrier mixes that officials said were about three days old.

On Monday, authorities arrested Deborah Sue Culwell, a 54-year-old Coachella resident they had identified as a suspect earlier that day. They took her into custody at her home, where they also found and confiscated 38 other dogs living in a “state of disrepair,” NBC Los Angeles reported. She’s facing seven counts of felony animal cruelty.

The bagged puppies — which would each fit snugly in the palm of a human hand — survived, thanks to a passerby who found them just in time. They’re now about a week old.

“We’re talking about seven pups tossed in the garbage like they were trash,” John Welsh, a spokesman for the animal services agency, said in an interview.

“It’s a pretty serious case as far as animal cruelty goes.”

Typically, animal cruelty cases in the Southern California county don’t result in much jail time, he said, but because this case is so egregious, it may be an exception.

It’s the second case of puppy dumping in a month, reported the Palm Springs Desert Sun, noting a March incident when animal services found two puppies in a trash bin at a recycling center in the same county.

But last week’s case was notable because authorities rarely catch someone in the act of abandoning an animal. The head of animal services, Chris Mayer, said he has talked with the district attorney’s office about building a case.

“There is no excuse for dumping puppies,” Mayer said in a statement, adding that the woman could have easily taken the dogs to a shelter.

"This was a shameful act.”

It was nearly a deadly one, too.

The plastic bag was sealed when the woman threw it away — plus, it was a blistering day in Coachella, the city that shares a name with a music festival in the desert nearby, with temperatures reaching the upper 90s that afternoon. The puppies were dehydrated and malnourished.

If a man, whom police identified only as “John,” hadn’t passed by soon after and heard the dogs’ cries, they could’ve died, Welsh said.

“He just happened to be in the right spot at the right time,” he said.

John was apparently rummaging through the trash when he found the bag and took it inside the auto shop, the animal services news release said. Veterinarians treated the puppies, and animal services transferred them to a local rescue group that is nursing them back to health.

“The Good Samaritan played a major role in saving theses puppies’ lives,” Mayer said in the statement.

"His actions were humane and heroic.”

In an interview with a local television station, John, who also declined to be named on air, said the animals were panting and in pain when he found them.

“I was kind of in shock to see the way that she threw it,” he said. “Carelessly, without emotion, like it was just a regular old bag of trash.”

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