HARRISBURG, Pa. (AP) – The FBI is investigating how Gov. Tom Wolf’s administration came to issue permits for construction on a multibillion-dollar pipeline to carry natural gas liquids across Pennsylvania, The Associated Press has learned.

FBI agents have interviewed current or former state employees in recent weeks about the Mariner East pipelines, according to three people who have direct knowledge of the agents’ questions.

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All three spoke on condition of anonymity.

When permits were approved in 2017, environmental advocacy groups accused Wolf’s administration of pushing through incomplete permits that violated the law.

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Wolf’s administration is declining comment. It has said in the past that the permits contained strong environmental protections and it denied forcing the Department of Environmental Protection to issue them.

The chief federal prosecutor in Harrisburg, U.S. Attorney David Freed, declined comment.

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