DARIEN (AP) -- A police officer has been charged with assaulting another woman during a country music concert at a western New York venue last summer.

The Genesee County District Attorney's Office tells The Buffalo News that the charge against 47-year-old Kelley Alcorn of Grand Island has been upgraded from harassment to assault. 

Alcorn, a member of the Niagara Falls Police Department, pleaded not guilty to the higher charge Wednesday in Darien Town Court.

Prosecutors say a woman from Farmington in Ontario County accused Alcorn of an unprovoked attacked that left the woman with bruises and a concussion during a concert at Darien Lake on Aug. 25.

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