An inmate faces additional time for threatening a federal judge.

Larry Boyd Wren, II pleaded guilty before a U.S. district judge in Amarillo Thursday to one count of mailing a threatening communication.

The 40-year-old wrote a letter to U.S. District Judge Sam R. Cummings to express his dissatisfaction with his incarceration while in the Brown County jail.

Wren made a threatening comment in the letter, and mailed it to Judge Cummings at the Federal Courthouse in Lubbock.

He faces a maximum penalty of 10 years in federal prison and a $250,000 fine.