A former Marine apparently distraught over his treatment by the federal Veterans Administration shot himself to death Monday inside the offices of Rep. Tom Lantos.
Lantos, a Democrat, was not in the office.
Victor Francis, 40, shot himself once in the chest and was declared dead upon arrival at Mills Peninsula Hospital.
Police spokesman Terry Reidy said the man entered the offices about midday and talked briefly with a woman working in the lobby.
"The gal said he had a handgun and [she] said, 'Don't fire that.' Then he fired one round into his chest," Reidy said. "He was known to the office. He had some kind of disagreement with the staff there over disability."
In a statement, Lantos said Francis was a former Marine "who served during the Vietnam era" and may have been suffering from post-traumatic stress syndrome. He came to the office "to work with a member of my staff on a Veterans Affairs matter," Lantos said.
"This appears to be a tragic personal incident, but it does not appear to be violence directed against me or any member of my office staff," Lantos said.
He said his office had worked on Francis' behalf for an extended period of time, but that "there had been no previous problems in his relationship with our office."
Roy Casstevens, a paralegal who works in an office next to Lantos', said workers in his office were ordered not to leave after the shooting.
"Somebody asked me if shots were fired. I said, 'I don't think so.' We didn't hear anything," Casstevens said. "Then the building manager said to stay in here, so we did."
Lantos, a native of Hungary, has represented a Northern California district since 1981 and is co-chairman of the congressional Human Rights Caucus.
In the early 1990s, the Democrat led an investigation of mismanagement at the Department of Housing and Urban Development.