Spanish police said on Tuesday that authorities seized 11 tons of cocaine inside shipping containers and arrested 20 people in two separate operations against drug trafficking.

The head of the Drug and Organized Crime Unit of the Spanish police, Antonio Martínez Duarte, said during a press conference in Madrid: "In one week, we managed to seize 11 tons of cocaine."

He added: "The seized drugs came from Colombia via Ecuador and were found in containers that arrived at the ports of the city of Vigo in the northwest of the country and Valencia in the east."

He also explained: "The first operation allowed the police to seize 7.5 tons of cocaine hidden in frozen tuna slices in the city of Vigo, while the second operation, which took place in the city of Valencia, enabled the seizure of 3.4 tons of cocaine hidden in false bottoms of marine containers."

He added that "the criminal organization used a frozen seafood company as a front to bring drugs into Spain."

He also confirmed that "twenty people were arrested in these two operations between the end of November and the beginning of December."