A female worker from Wag, a dog-walking service app, is under investigation for animal cruelty.

Angela Composto from Miramar, Florida told the New York Post that she hired a woman by the name of "Hannah" to take her Yorkshire Terrier, Bella, 8, and a Cavalier King Charles Spaniel, Chloe, 8, out for a routine walk back on October 20.

A Miramar Police Department incident report said Composto's home security camera captured Hannah returning with the Terrier pup looking "non-responsive and limp."

Composto, 52, had hired the dog walker through the app while she was out of town. Hannah arrived at 7:30 a.m. to pick up the dogs and returned at 8:18 a.m.

Since Wag workers are required to provide updates, Hannah sent a snapshot of both dogs with their tongues out and wagging their tails to assure their owner that the walk went "fine."

In an update however, Hannah mentioned that Bella became "startled" and "took a fall" during the walk when Chloe chased after a bird. The walker said she put both pups inside their cages and that she would "stay a while" to ensure Bella was okay.

Composto and her attorney, Susan Chana Lask, confirmed that the app contacted the dog owner at 9:30 a.m. and reiterated Bella's fall but said that Hannah was "currently at the home." Composto decided to check the surveillance video remotely and saw that Hannah had already left the home at 8:24 a.m., indicating that she only stayed for six minutes which contradicted her earlier statement about staying a while.

The footage also showed Hannah pacing around the driveway for an additional six minutes while talking on the phone before leaving the premises.

You can watch Composto's video surveillance here.

Wag then dispatched another walker to check on Bella after notifying the owner that the pooch may have gotten winded.

The second walker arrived at 10:17 a.m. and discovered Bella was dead inside her crate.

Composto was devastated and said:

"I wanted to scream, and I burst out crying. I couldn't even breath."

"I can't get it out of my mind that [Hannah] possibly could've saved [Bella] … and I'll never know if Bella was alive and just needed to get to a vet … or if she was already dead."

She added:

"I couldn't understand how a little dog goes out on a walk and comes back dead."

An investigator for the incident wrote in the report:

"[Hannah] then leaves Bella in her bed to suffer and die."

Wag has been plagued with accusations of losing or killing at least 15 pets while under the care of dog walkers hired through the app.

A petition for Wag to stop animal cruelty began circulating early last year after many complaints.

The Miramar PD looked into Bella's death in February – two months after the Post reported the incident – and contacted Hannah and her attorney, Sherri Romano, who claimed the death was an "accident."

However, investigators believe Hannah's accounts were not adding up.

A supplemental case report read:

"The statement given to this detective had many questions. It says the dog took a fall. Then it says the dog was jolted."

"In the statement it says when Hannah got back to the residence with both dogs, she realized the terrier was injured. However the video shows Hannah panicked trying to open the door and carrying a motionless dog back to the residence."

The report continued:

"The investigation revealed that [Hannah], who had the care and custody of Bella, took two dogs on a walk. [Hannah] brings the dogs back from their walk with Bella injured and motionless. Hannah gives no explanation of the injuries that would be consistent with the necropsy report of cause of death,

A copy of the report conducted by the University of Florida obtained by the Post revealed that Bella sustained a skull fracture and that her head and neck have been bruised.

The report also indicated that there was a "short time frame from injury to death."

Wag issued a statement saying that Hannah had been removed from the platform following the incident.