TRENTON, N.J. (AP) — The head of the Transportation Committee in the New Jersey Assembly says Gov. Chris Christie hasn’t adequately explained his claim that a New Jersey-New York rail tunnel could run $5 billion over budget.

Assemblyman John Wisniewski said Thursday that he found no justification for Christie’s cost overrun estimate in hundreds of pages of documents provided by the administration.

The Democrat got the documents Wednesday through an open public records request.

Christie canceled the $8.7 billion tunnel project, saying the state can’t afford the cost overruns.

Christie estimated them at $2 billion to $5 billion or more. U.S. Sen. Frank Lautenberg and other tunnel proponents have said the number is likely far lower.

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