A Rio de Janeiro snack bar owner was making savoury pastries from dog flesh after rounding up strays and beating them to death.
Officers are investigating a fast-food bar after reportedly finding cartons containing the remains of stray dogs, according to police.
The hounds are said to have been killed by blows to the head and their meat used for fillings of 'pasteis' a traditional Brazilian-Portuguese pastry which is deep fried and usually made with ground beef mince and cheese.
Police sources say that the snack-bar owner Van Ruilonc admitted to making the snacks from dog meat, saying that the animals were strays he had taken from the streets of Rio de Janeiro.
The 32-year-old is said to be one of a group of Chinese businessmen who own several pastry houses in the Brazilian city as well as one at the tourist destination of Copacabana.
The dog-meat pasty discovery came to light when police investigated claims that trafficked Chinese workers were forced to live and work in slave-like conditions, according to a Mail Online report.
At the restaurant in Rio's northern district of Parada de Lucas, police found a cage at the back of the building were workers were kept, and made to work 18 per day without wages.
Public prosecutor Guadalupe Louro Couto said: "I've seen lots of bad things, but what I saw in that pastry house was worse than everything. To start with, there was a cell, like a jail, with bars and padlock, set up inside the snack bar, where the worker was imprisoned.
"Apart from this, he lived with the stench of dead dogs, which were kept in the same room. I couldn't stand it. I started to feel ill and asked to leave.
"When we started to open the polystyrene boxes, we saw the frozen dogs.
"We were perplexed. There were various crimes being committed there."
The Chinese city of Guangxi Yulin holds an annual "Lychee Dog-Meat Festival". The controversial traditional festival draws howls of protests from animal protection activists.
The people in Guangxi Yulin believe in "eating dog meat, drinking lychee wine" on the day of summer solstice. In their views, this helps to improve the body's ability to resist diseases.