A western Michigan man has pleaded guilty to threatening presidential hopeful Sen. Cory Booker over the phone last year, according to an FBI news release.

Rick Simmons, 52, of Kentwood appeared in court Wednesday and admitted to making the call on the evening of Oct. 26 to Booker's office. He left a vulgarity-filled voice mail message, including threatening to "put a 9mm" into the senator's face.

"No individual, whether a public official or a member of the public, deserves to field threatening messages designed to dehumanize, intimidate and terrorize," said U.S. Attorney Andrew Birge of the Western District of Michigan.

Simmons faces a maximum of five years in prison, three years of supervised release and a $250,000 fine.

"The FBI works closely with the U.S. Capitol Police to investigate threats to harm or kill public officials wherever those threats originate," said FBI Detroit Field Office Special Agent in Charge Timothy Slater.

"In this case, the targeted individual was a senator, but we remain committed to safeguarding the rights of all individuals."

A sentencing hearing is scheduled for June 5.

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