The 14-week-old puppy, named Egg, died at his owner's home and his "body was disposed of", a NSW Police spokeswoman said on Thursday afternoon.

News of Egg's death comes a day after his owner, a 29-year-old man, was charged with making a false report to police, after he claimed the puppy was stolen during a late-night armed robbery at Sydney Olympic Park.

At the time of Egg's disappearance on February 9, the man allegedly told police he was walking the puppy near the corner of Australia Avenue and Parkview Drive about 10.30pm when he was confronted by three men who were armed with knives.

The man allegedly told police the offenders demanded his wallet and backpack, which he handed over to them.

As the offenders were leaving, they also grabbed Egg and ran away, the man told police at the time.

He even provided a description of the alleged offenders to police, saying they were of Mediterranean or Middle Eastern in appearance, and aged about 30. Two of the men were said to be of a slim build and the third man was of a large build with a bald head and a goatee, he claimed.

Police launched an investigation into the reported robbery and asked for the public to keep a look-out for Egg, who was described as being a smaller breed of pug and wearing a red-coiled collar when he went missing.

The investigation took a bizarre turn on Tuesday night when Egg's owner went to Auburn police station where he was questioned by officers from Flemington Local Area Command.

Police then issued the man with a future court attendance notice for false representation resulting in a police investigation. He is due to appear in Burwood Local Court on April 6.

On Wednesday morning, police still did not know where the dog was, and issued a new public appeal for information.

On Thursday afternoon, the search had been called off, the police spokeswoman said.

Police from the Flemington Local Area Command now say the dog "was not stolen, but died at the owner's home and his body disposed of", the spokeswoman said.

She said no further details were known about how the dog died, where the body was disposed of, or why the owner allegedly made a false report to police.

smh.com.au