Sean Patrick Cirillo called Ms. Greene’s office and told staff members about his plans to kill the politician, the F.B.I. said. He faces a maximum of five years in prison.An Atlanta man pleaded guilty on Tuesday to making death threats against Representative Marjorie Taylor Greene of Georgia.The man, Sean Patrick Cirillo, 34, made two threatening phone calls on Nov. 8, 2023, to Ms. Greene’s Washington, D.C., office, spoke to staff members and said that he planned to shoot the politician in the head, an F.B.I. agent said in court documents.“I’m gonna kill her next week,” Mr. Cirillo said, according to recordings of the phone call that were reviewed by the F.B.I. “I’m gonna murder her.”Mr. Cirillo pleaded guilty in U.S. District Court in Atlanta to one count of transmitting interstate threats. He will face a maximum possible penalty of five years in prison when he is sentenced on Nov. 7.“Threatening to kill a public official is reprehensible,” Ryan K. Buchanan, the U.S. attorney for the Northern District of Georgia, said in a statement. “Our office will not tolerate any form of violence, threats or intimidation against public officials.”In a statement, Mr. Cirillo’s lawyer, Allison Dawson, said that Mr. Cirillo had struggled with mental health issues and was not on his prescribed medication at the time of the incident.Ms. Greene’s office did not immediately respond to requests for comment on Tuesday.After Mr. Cirillo was arrested, Ms. Greene said in a statement to Atlanta News First: “Threats to murder elected officials should never be tolerated.”During his phone calls to Ms. Greene’s office, the F.B.I. said, Mr. Cirillo said that he was focusing on Ms. Greene through the sight of a sniper rifle. He also threatened to kill her staff members who picked up the two calls, which he made on Nov. 8 at 1:33 p.m. and 5:36 p.m., the F.B.I. said.The next day, when the F.B.I. showed up at Mr. Cirillo’s home by tracking his phone number, Mr. Cirillo admitted to making the calls, said he had made them to “get attention” and added that he had called “multiple other people as well including other members of Congress,” court records state. It is not clear who else received Mr. Cirillo’s calls.Mr. Cirillo’s guilty plea is the latest event in a recent pattern of threats toward political figures. Last week, a man was charged with threatening to assault and kill federal officials, judges and state employees across several states, including people involved in the prosecution of former President Donald J. Trump.In California, some elected officials said they were rethinking public office in light of increasing harassment.Kirsten Noyes More