Manhattan's top prosecutor says it's "premature" to say how confident he is that a former stock clerk is the person who killed a boy who vanished in 1979.

District Attorney Cyrus R. Vance Jr. also declined to comment Thursday on whether Pedro Hernandez's arrest clears two other men who had been eyed in the case.

Hernandez was charged last week with murder after police say he confessed to strangling Etan Patz.

Hernandez hasn't entered a plea. His lawyer says he's schizophrenic.

Vance says prosecutors are working on the case "in a measured, thoughtful, impartial manner."

A civil court declared another man responsible for Patz's death: a convicted child molester in a Pennsylvania prison. Then last month, investigators dug up a basement linked to a handyman. Neither was charged.

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