Authorities say a Fort Myers man threatened to kill an assistant U.S. attorney as revenge for prosecuting a fellow gang member.

Dylan Ray Langley, 24, pleaded guilty to mailing death threats.

Langley, who was already in state prison for armed robbery, threatened to kill the prosecutor's family. 

Investigators say Langley thought by threatening a federal official, he might be moved from state to federal custody. Authorities say he changed his story and said he had no intention of actually carrying out the threats after an agent explained he would still have to serve a state sentence first.

Langley now faces a maximum penalty of 10 years in federal prison after he completes his state prison sentence.

This case was investigated by FBI, the U.S. Marshals Service and the Florida Department of Corrections.

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