Secret Service Agent Dies Training at Bush Compound in Maine

Keith Mills, a Secret Service officer who protected the late President George H.W. Bush and former President George W. Bush, died Sunday, April 25, during training at the Bush Compound in Kennebunkport, ME.

An autopsy has been conducted, but the cause of death was not released.

Mills' death is considered a line-of-duty death, seacoastonline reports.

In a statement, former President George W. Bush said he and his wife Laura "were saddened by the sudden loss of Keith Mills." Bush called Mills a "dedicated public servant and exemplary member of the United States Secret Service.