ELKINS, W.Va. -- A Marshall County man has been indicted on charges he threatened to kill President Obama and the first family in a letter filled with profanity and racial slurs.Ryan Kirker, 20, of McMechen, could face as many as five years in prison and a $250,000 fine if convicted.His arraignment is set for Tuesday before U.S. Magistrate James Seibert in Wheeling.U.S. Attorney William Ihlenfeld said Kirker threatened the president in an April letter that was sent to the White House and that closed with the phrase, "KKK forever." The case was investigated by the U.S. Secret Service.An affidavit from a U.S. Secret Service agent says forensic experts also determined that Kirker had written about plans to kill Obama in a March 28 letter to someone named John. Special Agent Ken Skaggs said indentations in the paper linked the two letters.In the March letter, the affidavit says, Kirker tells John to meet him so the two can travel to Washington, D.C. That letter mentioned a specific weapon and Kirker's ability to obtain armor-piercing ammunition, as well as the fact that "the feds" had previously visited Kirker's home to investigate a third letter.Skaggs confirmed that he and other Secret Service agents visited the family's home in June 2012 to investigate an anonymous threat sent to the White House in April 2012. Kirker remained at the Northern Regional Jail on Wednesday. His attorney didn't immediately comment on the indictment.