The U.S. Department of Justice announced the charges Wednesday. Its statement said 57-year-old Lucy Richards of Tampa made the threats because she thought the December 2012 shootings in Newton, Connecticut, were a hoax.
The child's parent now lives in South Florida. The department didn't release the parent's identity or exact location and didn't return calls seeking more details.
Richards was arrested and charged with four counts of transmitting threats. Each carries a maximum term of five years in prison.
She awaits an initial court appearance Dec. 19. It's not immediately known if she has an attorney.
The Sandy Hook shootings left 20 children and six adults dead.
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