CANTON, Mass. (AP) - A biology professor charged with killing three of her colleagues at an Alabama university has been indicted in the 1986 shooting death of her brother in Massachusetts.

Norfolk District Attorney William Keating announced Wednesday that Amy Bishop had been charged with first-degree murder in the death of her 18-year-old brother, Seth.

Authorities had originally ruled her brother's shooting an accident. But they reopened the case after Bishop was charged in February with gunning down six of her colleagues at the University of Alabama-Huntsville, killing three.

Bishop had told police who investigated her brother's death that she accidentally shot him while trying to unload her father's shotgun in the family's Braintree home.

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AP-NY-06-16-10 1602EDT