Someone put nine puppies inside an empty dog food bag and sealed it with duct tape, San Diego Humane Society officials said.
The puppies, believed to be Shar Pei mixes between 10 to 14 days old, were found at Kit Carson Park on Thursday.
Bill Dixon, the man who found the Ol' Roy dog food bag, brought the puppies to San Diego Humane Society’s Escondido Campus.
"The bag was sealed with red duct tape and there were some air holes cut," said San Diego Humane Society Officer Serena Boney.
"They were all very hungry," she added. "They were trying to nurse on the towels we were wiping them down with."
The puppies were bathed and given food and water before being placed in foster homes, officials said.
Dixon is fostering three of the puppies.
"It was anger. It was strong anger," Dixon said, recounting the moment he found the sweet puppies. "It is shocking and it's heartbreaking. Luckily the puppies were found when they were."
The person who abandoned the dogs may face criminal charges.
Investigators are expanding their search for security video to places surrounding the park. It's believed whoever dropped off the dogs did so within a few hours of them being found.
The San Diego Humane Society wants to use the incident to remind the community they will take in any litters, no questions asked. They will also spay the mother for free.
Crime Stoppers is offering a reward of up to $1,000 for information that leads to an arrest in this case. Anyone with information can call the organization's anonymous tip line at (888) 580-8477 or visit the Crime Stoppers website at sdcrimestoppers.org for more information on how to send anonymous web and mobile app tips.