NASHVILLE, Tenn. (AP) — A federal grand jury toughened the charges against three anti-war protesters who authorities say cut their way through three security fences and spray-painted slogans on the walls of a nuclear weapons plant in Tennessee.

An indictment released Thursday in Knoxville charges an 82-year-old Roman Catholic nun with Sisters of the Holy Child Jesus, a gardener and a housepainter with “depredation” of the Y-12 National Security Complex in Oak Ridge. The charge carries a maximum penalty of 10 years in prison.

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