Hoboken, New Jersey - A devastated dog owner and his neighbors have been on a desperate search for answers in the case of a dog sitter who may have caused his pup's death.

Leaving your fur babies behind when you go on vacation is stressful enough without the added element of a psycho dog sitter. It takes time to develop trust but, if this horrific case is anything to go by, even a trusted sitter can turn out to be an imposter.

Diego Chaves recently left his canine companion in the care of a sitter named Micaela, who he had employed several times in the past with no prior issues.

His trust in "Micaela" was soon to be diminished when the sitter, who other clients know by a different name, lost his dog Mac. Sadly, the perfect pup ended up passing away at a local vet one day later.

On July 2, Chaves left his goldendoodle in the hands of Micaela, who he later found to be legally named Alyssa Tognetti. Chaves found the dog-sitter on the pet care app Rover, according to Hoboken Girl.

After using and trusting Alyssa's dog-walking and sitting services numerous times, Chaves felt comfortable leaving Mac in her hands.

That is, until she suddenly stopped responding to his messages on July 5, the date on which his dog was meant to have been returned to him.

Using the social media resources at his disposal, Chaves shared a since-deleted post on Facebook and Instagram, writing "Living a nightmare right now. I was waiting to pick Mac up this morning when the sitter stopped responding. The sitter's name is Micaela from Posh Pet Services in Jersey City."

In the now-viral post, which has wracked up tens of thousands of views and more than 17,000 likes, he continued, "If anyone has seen Mac, Micaela, or knows anything that could help find him or her, please let me know."

The Facebook post was updated early Thursday morning, with Chaves sharing that he received an alarming call from his vet that Mac was inexplicably found and brought there. Regrettably, the dog passed away before Chaves arrived at the facility.

Just before he received the sad news, Alyssa Tognetti finally made contact with Chaves via email, telling him that his one-year-old pup had jumped out of her car and took off in a mad dash down the street.

According to the email, Alyssa told Chavez that Mac jumped out of her car when she was dropping another dog off at its home, citing that she "didn't expect him to run out" of the open car door.

The sitter followed up by justifying why Mac was in her car to begin with, saying, "The only reason he was with me was because I wanted to be able to drop him off or be up front in time for you guys."

Alyssa Tognetti, who at that point still went by Micaela, then ended her email by expressing her deep regret and shame, telling Chaves she was "quitting watching dogs" because of the horrific incident.

While the search for Mac ended on a heart-wrenching note, the hunt for Alyssa – and answers – is still underway. Still not understanding the logistics of what happened, or why his young puppy suddenly died, Chaves started a GoFundMe to aid in the search.

The description reads, "Please help us in figuring out the events that led to the passing of our sweet boy, Mac, so we can ensure no one else has to go through this pain. All extra funds will be donated to local animal shelters, in Mac's honor, to help dogs in need."

Chaves did not immediately respond to TAG24's request for comment.

Community members have wondered whether the incident could be connected to a number of recent unsolved cases of dog neglect at the hands of what could be the same fake-named sitter.

"I really hope this woman goes to jail. Why was she not arrested for the dogs locked in her car last week?" Amanda Kocis Gallagher commented on Chaves' heartbreaking update. "And Rover should be accountable to an extent for allowing this sketchy woman to create multiple profiles with multiple names."

Last week, neighbors reported a dog walker to police who they believe was the same sitter.

"She had my dogs and several others left in a hot car in Brooklyn. She went by 'Michela' on Rover...She often took dogs to the parks around Newport [Jersey City]," said another dog owner Regan Newcomb on a post about Mac's disappearance.

Others also seemed to have had close encounters with the negligent dog walker, and detailed more occurrences online.

Rover has not commented on the sitter or the situation, but Newcomb believes her account on the app "has since been shut down."

The case is currently under investigation by the Jersey City Police Department, according to News12, while the community deals with the fallout and unease of an untrustworthy perpetrator having access to their homes and the care of their animals.

"Please keep an eye out," Newcomb warned. Meanwhile, Gallagher added "I hope she gets what’s coming to her."