A Goodwill collection center in Chattanooga, Tennessee, was doing a routine inventory of items people dropped off for donation last Thursday, when the workers got the shock of their lives.

Inside a cardboard box marked “stuff [sic] animals,” they indeed found animals, but they were certainly not of the stuffed variety.

Inside, workers found three frightened, exhausted puppies.

The three dogs, all female, were suffering from heat exhaustion and were covered in urine, suggesting they might have been in the box for some time.

The dogs were sealed into a cardboard box and left in the heat. Rescue workers found that temperatures inside the box reached almost 100 degrees Fahrenheit.

This is the box they arrived in.

So far, no one knows who did this, or why someone would ever think to do this to helpless puppies.

There is good news, though. They are making a swift recovery and are staying at the McKamey Animal Shelter.

They are estimated to be between nine and eleven weeks old and, despite their harrowing ordeal, are expected to make a full recovery.

(via WSBTV)

Authorities are still looking for whoever did this, though, and thanks to some donations, there’s now a $4,000 reward out for information leading to an arrest. If you’re in the Chattanooga area and think you might know something, please speak up!

But even if the person is never caught, the important thing is that these three pups are safe, and will hopefully be heading to happy new homes soon.