Updated at 2:27 p.m. ET
(CBS/AP) NEWARK, N.J. - Ambulances and law enforcement met a cargo ship at a New Jersey pier on Wednesday after a routine inspection led the Coast Guard to believe that stowaways were inside a container loaded in India.
Coast Guard spokesman Charles Rowe told CBS Radio News the container was loaded in India aboard the Cyprus-flagged Ville D'Aquarius. The manifest says the container was carrying machine parts to be unloaded in Norfolk, Va.
A Coast Guard team boarded the 850-foot-long vessel outside New York Harbor early Wednesday as the ship prepared to dock at Port Newark. During the routine inspection, the boarding party heard sounds coming from the container that indicated people may be inside, Rowe said.
The boarding party followed protocol and didn't open the container at sea in order to control the situation, Rowe said.
"We have no information on the individuals, and we're not 100 percent sure that there are people in there until we open it," Rowe told CBS New York station WCBS-TV.
Immigration and Customs Enforcement agents, Border Patrol agents and police officers from the Port Authority of New York and New Jersey met the vessel when it docked Wednesday morning, WCBS-TV reported. Several ambulances and hazardous-material crews were also on the pier.
Once the ship was docked, authorities began unloading containers to get to the one that the Coast Guard suspected might have people inside. Authorities planned to open the container once it was unloaded. The container is deep within the ship.
By midday Wednesday, all but one ambulance had quietly left the pier. Rowe said officials have inspected 80 of the 200 containers authorities believe could be carrying people. The ship has 2,000 containers altogether.
Drew Barry, of the Sandy Hook Pilots Association, said he boarded the vessel at 5 a.m., about 20 miles offshore.
Barry, who left the ship at around 9 a.m., said he thought it would take several hours, if not much of the day, to get to the part of the ship, below the hatch cover, where officials heard banging noises.
"There are at least 30 to 40 containers on top of the hatch cover, and I don't know how many more below it," Barry said. "If there are people down there, with no food and water for days, they're probably pretty desperate by now."
The Department of Homeland Security said in a statement Wednesday that officials are conducting a "thorough investigation of the vessel."
Meanwhile, a small boat was waiting in the water nearby in case anyone tried to jump off the vessel, CBS New York station WCBS-AM reported.
The ship began its voyage May 30 in the United Arab Emirates, then made one stop in Pakistan and two stops in India. Its last port before Newark was in Egypt on June 15.