Officials say an emotionally disturbed man breached security at one of the nation's busiest ports, boarded a ship and was found in the captain's cabin.

Officials are trying to figure out why Eric Carrero went unchallenged.

Authorities believe Carrero scaled a barbed-wire-topped six-foot security fence at the Port Newark marine terminal in New Jersey on Wednesday. A Port Authority of New York and New Jersey official says Carrero wandered around before he boarded the cargo ship and was discovered in the captain's bed about four hours later.

Carrero is undergoing a psychiatric evaluation.

It was the second recent security breach at a Port Authority facility. Earlier, a man swam to Kennedy Airport after his personal watercraft ran out of gas.

Port Newark handles more than 600,000 shipping containers annually.

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