Updated: 6:53 p.m.

A California man has been arrested for making threatening phone calls to Speaker Nancy Pelosi (D-Calif.).

The FBI’s San Francisco office has identified the man as Gregory Guisti, 48. He was taken into custody Wednesday at about noon Pacific time in San Francisco, said Patty Hansen, spokeswoman for the bureau’s office there.

Hansen said Guisti’s initial court appearance will be Thursday at 9:30 a.m. Pacific time, but she declined to comment on the charges.

“The FBI takes threats against elected officials very seriously,” she said.

The Associated Press cited unnamed federal officials who say the man “made dozens of calls to Pelosi’s homes in California and Washington, as well as to her husband’s business office, reciting her home address and saying if she wanted to see it again, she would not support the health care overhaul bill that was recently enacted.”

“One official said the man is believed to have spoken directly with Pelosi at least once,” the report continues.

Capitol Police spokeswoman Sgt. Kimberly Schneider told Roll Call that the Capitol Police worked with the FBI on the case, but she declined to comment further, as it’s an ongoing investigation.

Charges have yet to be announced.

“After an investigation into threats made against Speaker Pelosi, an arrest has been made in San Francisco,” said Brendan Daly, a spokesman for Pelosi. “The Speaker thanks the FBI, the Capitol Hill Police, House Sergeant-at-Arms and other law enforcement officials for their professionalism in this matter. She will have no further comment at this time.”

Jack Gillund, spokesman for U.S. Attorney for the Northern District of California Joseph P. Russoniello, said: “I can neither confirm or deny anything at this point.”