'My heart is bursting': Watch homeless Sydney man's emotional reunion with pet rat

A homeless Australian man left heartbroken when his rat was stolen has been reunited with his prized pet.

The Sydney local, known only as Chris, went viral this week after writing out a sign for passers-by at his usual spot at Pitt St mall, expressing his sorrow at losing his best friend Lucy.

Rat Lucy was snatched in an apparent act of cruelty by a woman who remains on the run. But while police are still working hard to track down the culprit, they have - much to Chris' relief - found Lucy.

And on Thursday, in an emotional makeshift ceremony at a local police station, the pair were reunited.

After double-checking that it was Lucy, Chris thanked police for their efforts.

"Yup, that's her. She's got the blind eye. She remembers me. Kiss kiss," he said.

"Sorry for putting you through the trouble of looking for her."

Chris said it was a wonderful feeling to have Lucy back and knew she was happy to see him. They then posed with officers for pictures.

Social media users thanked the officers for their work getting Lucy back to her proud owner.

"My heart is bursting!" one woman wrote.

The theft had left Chris distraught, who used a handwritten sign to appeal for help.

"My pet rat Lucy was stolen on Saturday. Lucy is black and white with a bit of brown," it said.

Lucy had been left sitting on a milk crate. A woman approached the man's belongings and took the rat.

A GoFundMe page for Chris has raised more than $1500.

Newshub.