PHILADELPHIA (CBS) — One of the largest cocaine busts in United States history happened Tuesday in Philadelphia. Federal authorities continue to comb a cargo ship at Packer Avenue Marine Terminal in South Philadelphia.

So far, they’ve seized 16.5 tons of cocaine — 33,000 pounds — which has a street value of more than $1 billion, the U.S. Attorney’s Office says. Investigators believe there is still a significant amount of cocaine remaining on the ship.

According to the U.S. Attorney’s Office, 16.5 tons of cocaine was confiscated from seven shipping containers, making it the largest drug seizure in the history of the Eastern District of Pennsylvania.

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