WASHINGTON (AP) — An Army doctor is under investigation after questioning on YouTube whether President Barack Obama is U.S.-born — then disobeying orders to report for duty in Afghanistan.

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Lt. Col. Terrence Lakin failed to report to Fort Campbell, Ky., on Monday, showing up instead at his old job in a clinic in the Pentagon. He was reassigned immediately to Walter Reed Army Medical Center while the investigation is under way.

Though officials in Hawaii verify that Obama was born there, so-called “birthers” claim he was born outside the U.S. and is ineligible to be president.

Lakin says he wants to see the birth certificate as proof Obama is his commander in chief and thus that the deployment order for Afghanistan is legal.

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