Uruguayan authorities have opened an investigation into a record cocaine seizure described as “the biggest blow to drug trafficking in the country’s history,” the navy said on Friday.

The navy seized four soy flour containers packed with bags of cocaine at Montevideo’s port.

An inventory of the first container found “3,089 bricks of cocaine each weighing 1.1 kilograms (2.4 pounds),” Navy spokesman Diego Perona told journalists.

That figure was later revised to 3,500 bricks, and the amount of cocaine found in just the first container already represents the largest seizure on Uruguayan soil.

“The drug has been detected in four scanned containers,” added Perona.

Uruguay is increasingly being used as a transit point for Latin American-produced cocaine heading to Africa and Europe.

The previous record was 3 tons found in a container destined for Africa at Montevideo’s port in November.

If all four containers hold the same amount it would mean more than 15 tons of cocaine.

The soy flour containers were destined for Lome, the capital of Togo. They were loaded on Tuesday from a ranch in the southwestern department of Soriano.

Authorities are questioning the soy company owner and truck drivers who brought the merchandise to the port in Uruguay’s capital Montevideo.

In August, German customs seized 4.5 tons with an estimated street value of $1.1 billion from a container that arrived in Hamburg from Uruguay. The manifesto said the container carried soybeans.

In August, 1 ton of cocaine was found in an eastern Uruguay seaside town.

That came after France in mid-May confiscated 600 kilograms of remarkably pure cocaine from a private jet that had arrived from Uruguay.

Colombia, Peru and Bolivia are the largest producers of coca leaf, the primary ingredient in cocaine.