It happened around 2 a.m. on Absecon Blvd. in Atlantic City.
Video shared with Action News shows a man walking up to the Humane Society and tossing a pit bull mix over the fence.
"He sits in the car for quite a while and then he gets out of the car, walks the dog over to the fence, picks the dog up and throws the dog over the fence," said Steven Dash, the shelter's executive director.
Officials say it's the fourth dog in recent months to be dropped off in the early morning hours, and they believe it could be the same person.
The Humane Society says the man drives a black Cadillac sedan.
Back on April 8, officials believe the same car pulled up and tossed three other pit bull mixes over the fence. Video also captured that incident.
3 dogs left outside overnight at NJ humane society
The animal has very distinct scarring on her back. Shelter staff believe it's an old injury - possibly a burn.
"That hair's not going to grow back. She's gonna wear those scars the rest of her life," said Dash.
She's not up for adoption yet because of the ongoing investigation, but Dash said that will likely change.
"She's a great dog. We think she's about 4-5 years, is our guess. She is just super chill. She loves people."
Anyone with information is asked to call the Humane Society of Atlantic County or the Atlantic City Police Department.
Officials want to remind those looking to surrender a pet to call their local shelter during normal business hours to find out the process.
Due to overcrowding, there may be an application process or a wait list involved.
There may be resources out there that allow you to keep your pet.
"Talk to your local shelters and rescue groups that'll help you keep the animal. Sometimes it's financial things. Sometimes it's medical things. And sometimes there's help out there," said Dash. "But if you really have to find a home for your animal, don't wait until the last minute."