Federal Police on Wednesday seized three tons of marijuana in Santa Teresa do Oeste, Brazil's southern state of Parana.
The drugs were found hidden in a truck shipping wheat flour.
The pair in the truck, 41-year-old Rosevaldo Maciel de Souza and 44-year-old Silvio Lane da Silva, were arrested. They admitted they were transporting the drugs from Paraguay to Brazil's largest city Sao Paulo.
The two, charged with drug trafficking, could face five to 15 years in prison if convicted.