Federal authorities have confiscated 16.5 tons of cocaine from a ship at a port in South Philadelphia.

The U.S. Attorney’s office reported the illegal drug was found in a ship at the Packer Marine Terminal on Tuesday, Fox 32 reported.

Officials estimate the seized shipment of 33,000 pounds of cocaine has a street value of over $1 billion.

The Attorney’s office noted some members of the ship’s crew had been arrested in the largest drug seizure in the history of the Eastern District of Pennsylvania.

Officials also said the search is still underway and they feel there may be even more of the drug hidden on board.

Before arriving at the Philadelphia port, the Mediterranean Shipping Company vessel stopped in the Bahamas, Panama, Peru, and Colombia, and was on its way to the Netherlands. The cocaine was likely loaded onto the ship while it wasa asea after it left Peru.

“A U.S. Customs and Border Protection and Immigration and Customs Enforcement Homeland Security Investigations-led multi-agency inspection of shipping containers aboard the MSC Gayane resulted in a substantial cocaine seizure in Philadelphia on June 17, 2019. Authorities continue to process the seized cocaine and continue its inspection aboard the vessel in the Port of Philadelphia. Authorities have made two arrests and will release a final tally, and additional details when this operation concludes,” said a statement from the U.S. Customs and Border Protection.

This is one of the largest drug seizures in United States history. This amount of cocaine could kill millions – MILLIONS – of people. My Office is committed to keeping our borders secure and streets safe from deadly narcotics. https://t.co/nWPfgpGqYa — US Attorney William M. McSwain (@USAttyMcSwain) June 18, 2019

Philly Mayor Jim Kenney also released a statement saying he is “thankful for the hard work” of local and federal authorities with the seizure.

“Every ounce of drugs we keep off the streets is helping to keep Philadelphians safe and alive. Mayor Kenney is thankful for the hard work of the Philadelphia Police Department, FBI, ICE, U.S. Customs and Border Protection, and the U.S. Coast Guard,” Kenney’s office said in a statement.

Follow Warner Todd Huston on Twitter @warnerthuston.