NEWARK, N.J. (AP) -- Two boys who disappeared from a state facility in New Jersey in 1975 have been added to the FBI's missing persons website.

Authorities say 12-year-old David Williams of Newark and 17-year-old Steven Anderson of Westville were roommates at what today is the New Lisbon Developmental Center. They had developmental disabilities and were unable to care for themselves without supervision.

They were last seen on April 7, 1975. An extensive search of the New Jersey Pinelands turned up nothing.

Williams would be 55 years old and Anderson would be 60 these days.

FBI Newark Special Agent in Charge Timothy Gallagher says no matter how long a child is missing, it will always be a top priority for the FBI.

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