The following is a list of some shootings at post offices:

Jan. 30, 2006 — A female ex-postal worker opens fire at a mail processing plant near Santa Barbara, Calif., killing six people before committing suicide, authorities say.

April 17, 1998 — Maceo Yarbough III, a 27-year-old letter carrier, fatally shoots a post office clerk in Dallas after they argue in a break room. He is found not guilty of murder by reason of insanity.

Sept. 2, 1997 — Jesus Antonio Tamayo, a 21-year postal veteran, leaves his counter at a Miami Beach, Fla., post office, gets a gun from his car, walks back in and critically wounds his ex-wife and a friend, who were waiting in line. Tamayo, 64, then goes outside and kills himself.

July 9, 1995 — Bruce William Clark walks up to his boss in a processing center in City of Industry, Calif., pulls a handgun from a paper bag and shoots him to death. Clark, 58, pleaded guilty to second-degree murder and was sentenced in 1996 to 22 years in prison.

March 21, 1995 — Christopher Green, 29, a former postal worker burdened with "a mountain of debt," kills four people and wounds another during a holdup at the Montclair, N.J., post office. Green was sentenced to life in prison in September 1995.

May 6, 1993 — Postal worker Larry Jasion kills one and wounds two at the post office garage in Dearborn, Mich., before killing himself.

May 6, 1993 — Fired postal employee Mark Richard Hilbun kills his mother, then walks into a post office in the Dana Point community near Los Angeles and shoots two workers, killing one. He was convicted of murder, attempted murder and other felonies and sentenced to life in prison.

Nov. 14, 1991 — Fired postal worker Thomas McIlvane kills four supervisors and wounds five employees at a post office in Royal Oak, Mich., and then killed himself.

Oct. 11, 1991 — Joseph M. Harris, a fired postal worker, kills a former supervisor and her boyfriend at their home in Wayne, N.J., then goes to the Ridgewood post office where he kills two mail handlers as they arrive for work. He was sentenced to death and was on death row when he died in 1996 after suffering a seizure in his cell.

Aug. 10, 1989 — Postal worker John Merlin Taylor of Escondido, Calif., shoots and kills his wife at their home, then drives to the Orange Glen post office, where he shoots and kills two colleagues and wounds another before killing himself.

Aug. 20, 1986 — Patrick Henry Sherrill, a part-time letter carrier in Edmond, Okla., kills 14 people in the post office there before taking his own life. Sherrill had a history of work problems and faced the possibility of being fired.