WASHINGTON (AP) — The Washington Post says it won’t distribute any more columns by Garrison Keillor because he didn’t reveal he was under investigation in his most recent effort.

MPR announced Wednesday it was terminating contracts with Keillor because of an allegation of improper conduct by someone he had worked with. MPR said it had learned of the allegation last month, and it had hired an outside law firm to investigate.

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Keillor said nothing about the investigation in his last column, in which he criticized calls for Sen. Al Franken to resign over allegations of sexual misconduct.

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Washington Post editorial page editor Fred Hiatt says Keillor’s column failed a basic transparency test.

The Post had syndicated Keillor’s column after his retirement from “A Prairie Home Companion.”

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