RIO DE JANEIRO, April 9 -- Brazilian police on Wednesday seized a record 48 tons of marijuana in a favela in Rio de Janeiro, uncovered by chance by a sniffer dog during a regular operation against criminal factions.

During the operation in the Complexo da Mare, a large complex of favelas in the north of the city, a dog named Hulk indicated there was something suspicious under an abandoned water tank.

An officer "discovered a bunker inside where this entire quantity of drugs had been hidden," said Lieutenant Colonel Luciano Pedro Barbosa, commander of the Canine Operations Battalion.

He told AFP the seizure was the largest in Brazil's history and "represents a financial loss of over 50 million reais (almost US$10 million; nearly RM39.87...