Officials did not find any stowaways after more than 24 hours of searching a ship at Port Newark where U.S. Coast Guard officials heard sounds coming from a cargo area during a routine inspection.
Authorities had suspected there may have been stowaways on board, but were not certain which container was the source of the noise. Inspectors worked throughout the day and then overnight checking containers, using X-Ray machines and K-9 units.
The Department of Homeland Security said Thursday that more than 160 containers were searched.
The ship, called the Ville d'Aquarius, originated in the United Arab Emirates on May 30 and stopped in ports in Pakistan, India and Egypt before arriving in the U.S.
Coast Guard spokesman Charles Rowe told NBC 4 New York that the agency was doing a routine boarding at 3 a.m. Wednesday as the ship was anchored in Ambrose Channel, the main shipping channel serving the Port of New York and New Jersey.
Inspectors "heard sounds coming from one of the containers in the hold consistent with the sounds of people inside," Rowe said.
Numerous agencies were alerted, and authorities began bringing containers onto the pier for closer examination.
The ship has 2,000 containers altogether.
Officials say they get stowaways in New York harbors about six times a year.
Speaking at an unrelated news conference, Andrew McLees, special agent in charge of Homeland Security investigations for U.S. Immigration and Customs Enforcement, said the ship's origin and itinerary prompted the initial search.
"The routing of the ship and the ports of call was what led to the actions," McLees said.
Michael Ward, the FBI's top official in New Jersey, said the response was appropriate given the port's vulnerability. The area is considered a prime potential target for terrorists.
"You're going to get a response like this any time you have these types of facts," Ward said. "It was an appropriate response which we did out of an abundance of caution."
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