Jae C. Hong / Invision/AP 1 / 6
Jae C. Hong / Invision/AP 1 / 6

CLAREMORE, Okla. (AP) -- Country music star Garth Brooks is suing an Oklahoma hospital, saying it reneged on a promise to name a building after his late mother in exchange for a $500,000 donation.

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Brooks' lawsuit against Integris Canadian Valley Regional Hospital in Yukon seeks the return of the December 2005 donation. The trial began on Tuesday.

Brooks says hospital officials showed him mock-ups of buildings bearing Colleen Brooks' name and told him his donation was earmarked for such a project.

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The hospital denies any wrongdoing and in court filings says Brooks' donation was "anonymous and unconditional."

Dressed in jeans and a black cowboy hat, Brooks shook hands with lawyers and made small talk before proceedings began on Tuesday. He was accompanied by his wife, country singer Trisha Yearwood.

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