Image copyright EPA Image caption Carabinieri stand guard as police officers search a meatpacking complex in Rio de Janeiro.
Authorities in Brazil say they have found more than 100 tonnes of horse meat laced with chemicals.
Police said the meat – a combination of horse and horse and horse-lion meat – was sold as beef products at supermarkets and in restaurants in the country.
A man arrested has been linked to horse meat distributor Camorra.
Police said nearly 50 people – including corrupt civil servants and businessmen – were detained as part of the investigation.
“The level of contamination is truly shocking,” said Henrique Carlos from the federal prosecutor’s office.
“The shipments all came with food-grade meat names, but with horse meat ingredients.”
Image copyright Reuters Image caption Horses are a key part of the Camorra’s business model
The arrest of the man linked to the imported horse meat comes after Brazilian President Michel Temer pledged to “crush” crime within the powerful Camorra mob, which controls Naples.
Italian police on Monday announced the arrest of three members of the Camorra as part of the operation launched in June.
Brazil’s state-run agriculture ministry said in a statement that about 50 tons of horse meat, ‘better suited for grazing’ were found at a warehouse in the outskirts of Rio de Janeiro.
“They were trying to buy more horses from North American and European stallions,” said investigator Paulo Ferreira from the federal investigative agency IBAMA.
Carabinieri officers and investigators searched an industrial warehouse in the southern city of Curitiba and a slaughterhouse in Rio de Janeiro.
Image copyright Reuters Image caption Brazilian President Michel Temer pledged to crack down on crime by criminals
Police said the horse meat was processed in Brazil, but seized samples from Romania, Italy and Germany as well as France.
According to the state-run news agency Agencia Brasil, there were accusations that other agents who imported horse meat were still working for two other companies implicated in a previous investigation.
Image copyright AFP Image caption Brazilian authorities have found more than 100 tonnes of horse meat laced with chemicals
The latest investigation is not the first time Italy’s Camorra has been investigated for its practices.
As Italy joins Russia, Australia and Ukraine in banning horse meat imports from Brazil, sources at the national farm office insist Brazilian Agriculture Minister Blairo Maggi’s fears that horse meat is destined for the EU are unfounded.
“I think that’s not the case,” Agence Brasil quoted Vasila Fleury, director of the agricultural ministry’s animal agriculture bureau, as saying.
Instead, she pointed to illegal sales of horse meat to vet shops in the past as reasons for the Government to temporarily halt any imports.
Image copyright EPA Image caption The horse meat in Brazil may have been being used as a substitute for beef when it was cut up
“It’s a matter of a black market and their lack of knowledge about this type of meat is what they are dealing with.”
The Brazilian Attorney General’s office is not ruling out an investigation in connection with Italy.
According to an IBAMA statement, authorities are analysing the tonnes of horse meat seized.