A Melbourne father is angry a "low life" snuck into his backyard, stole his family dog of 10 years and left it bleeding in the streets.

Muffin, a Silky Terrier cross Pomeranian, was returned to John Kotowskyj last Thursday, more than a year after he was presumably stolen.

In the video above: Melbourne dog thief caught on CCTV stealing 18-month-old staffy

But the sudden reappearance is shrouded in mystery, with vets unable to tell the family what really happened.

“The story I was told is that they can’t tell you who, what, where," Kotowskyj told 7NEWS.com.au.

The family's dog of 10 years was found a few suburbs away in a critical condition, requiring life-saving surgery to remove an eye.

"His right eye was ripped out of its socket, it was a pretty awful injury." Credit: Supplied

"His right eye was ripped out of its socket, it was a pretty awful injury.

"I had a mixture of feelings. You’re glad you're going to be reacquainted, sad that he’d been so severely injured.

"There’s also a tinge of anger because of the whole circumstance."

Disturbing trend

The pup went missing, presumed snatched from the family's backyard, in July 2018.

Although the family was devastated, Kotowskyj said they didn't put up signs, or offer a reward.

Chevron Right Icon 'It's a low life thing to do.'

“Muffin had a collar with my telephone number so the person who took it would know it was owned by someone," he said.

"If it was injured in a road accident it would be returned by the vet.

"And so once he didn't turn up, it led us to the conclusion that someone had nabbed him."

Muffin went missing, presumed snatched from the family's backyard, in July 2018. Credit: Supplied

Kotowskyj says Muffin's disappearance isn't an isolated incident.

“There are a lot of smaller dogs that go missing in the area."

Around the same time, a similar white dog went missing just one block away from the family's home.

Four months later, the other missing dog reappeared in Cranbourne in Melbourne's southeast with a new collar and lead.

Chevron Right Icon 'They’re expensive to obtain but they’re also very easy to take.'

Without any definitive answers, he believes that, because another dog went missing in similar circumstances, someone is "targeting the dogs and on-selling them".

Pomeranians cost more than $1,000, with pedigree breeds selling in the thousands.

'Easy to take'

“They’re expensive to obtain but they’re also very easy to take," Kotowskyj said.

The RSPCA says the incident is a stark reminder for responsible owners to ensure their pets are securely contained.

“Microchips also greatly increase the chance of being happily reunited with your lost pet, but only if the details are correct," a spokesperson said.

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Kotowskyj says "it’s a low life thing to do. They may not understand the implications of the act."

"They don’t interact with the families and they don’t understand the distress it causes."

Although both of John's daughters have now moved out of home, Muffin is settling back in.

"The pain killer patch is off and he looks like he’s going to be fine."