HAGERSTOWN, Md. (AP) — An inmate who mailed a letter filled with powder to a former judge has been sentenced to five more years in prison.

Robert Turner, an inmate at North Branch Correctional Institution, was convicted on Thursday of manufacturing a fake destructive device. He mailed the letter, filled with crushed over-the-counter medication to former John P. Corderman in 2008.

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Turner, 38, said he wanted to bring attention to a motion to modify his 50-year sentence for first-degree murder.

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Corderman testified that he first feared the powder was anthrax.

He was injured in 1989 when a pipe bomb sent to his home exploded.

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