New York's police chief said Thursday that a man has been detained after implicating himself in the disappearance of a young boy in 1979, an unsolved crime that has haunted Americans ever since.

"An individual now in custody has made statements to NYPD detectives implicating himself in the disappearance and death of Etan Patz, 33 years ago," Police Commissioner Raymond Kelly said in a statement.

Further details were expected to be made public later Thursday, he said.

The possible breakthrough follows a surprise decision in April to reactivate the cold case.

Teams of FBI and New York police officers searched the basement of a house in Manhattan' SoHo district near where six-year-old Patz was last seen, as he went to catch his school bus.

The search ended with no announcements about any important discoveries, although debris from the excavation of the basement was removed for analysis.

Patz's vanishing shocked the country, prompting parents nationwide to step back from previously relaxed attitudes about letting children go out alone in the street.