Authorities were conducting a routine inspection aboard the MSC Carlotta last month when a teal shipping container caught their eye: The pins that held the containers’ doors in place appeared to have been doctored.

The Carlotta, a container ship, had just arrived in Newark, New Jersey, from Buenaventura, Colombia, and the container was supposed to contain dried fruit. Instead, officers opened the doors to find 60 tightly wrapped bundles of white powder, each the size of a small trunk.

The bundles turned out to be 3,200 pounds of cocaine, the largest drug shipment to be intercepted at Port Newark in a quarter-century, a bounty worth $77 million on the street, authorities said Monday.

The discovery of the shipment underscored the reality that legal ports of entry remain the main channel through which illicit drugs flow, even though President Donald Trump has contended drugs are pouring over the unsecured sections of the southern border.

The seizure Feb. 28 also suggested the city’s market for cocaine was resurging, officials said, after several years during which heroin and fentanyl, a powerful synthetic opioid, had dominated New York’s illicit drug scene.

Ray Donovan, head of the Drug Enforcement Administration office in New York City, said dealers have begun combining fentanyl with cocaine, creating a new and deadly product. He said the giant cocaine shipment was a sign traffickers were pushing “to build an emerging customer base of users mixing cocaine and fentanyl.”

Investigators from the Department of Homeland Security were trying to determine where the drugs came from, and how they ended up in Newark. Authorities said Monday no arrests had been made.

The port in Newark is one of the country’s largest and is a hub for illicit drugs from China and Mexico to enter the United States.

Cocaine has taken a back seat in recent years to opioids like heroin and fentanyl, officials said. Heroin is often cut with fentanyl to make it more potent, a trend that has caused an increase in overdose deaths.

This article originally appeared in The New York Times.