Bombings. Butyric acid attacks. Sniper shootings. Letters filled with fake anthrax. These are some of the tactics used over the years by antiabortion extremists.
The slaying of Dr. George Tiller in his Kansas church Sunday was part of a decades-long history of domestic terrorism aimed at abortion providers, carried out by a small minority of the much broader and generally peaceful movement that opposes abortion.
The National Abortion Federation, which supports abortion rights, has documented more than 6,100 acts of violence against abortion providers in the United States and Canada since 1977. The group classifies as "violent" not only the acts of murder, attempted murder, bombing and arson, but also vandalism, burglary and stalking, among others.
Tiller's slaying appears to be the eighth of an abortion clinic worker in the U.S. or Canada and the fourth of a doctor. A fifth doctor was shot but survived -- as did Tiller in a previous attack.
These illegal tactics -- denounced by many peaceful antiabortion activists -- multiplied in the 1980s, as the broader movement shifted away from pressuring the women who were having abortions to the medical personnel providing them, according to Carole Joffe, a sociology professor at UC Davis.
The shift in emphasis was a smart public relations move for those who oppose abortion, casting women as victims while exploiting public uneasiness over doctors who performed the procedure. Those public sentiments stemmed, in part, from the existence of ethically sketchy, "back-alley" abortion providers in the era before the Supreme Court's 1973 ruling that legalized abortion, Roe vs. Wade.
Clinics and clinic workers were subject to vandalism, bombings and death threats through the 1980s, but it was not until March 1993 that the United States saw the first known political slaying of an abortion provider.
Dr. David Gunn was shot during an antiabortion protest at a Pensacola, Fla., clinic. The year before, a "wanted" poster with Gunn's photo and home phone number had been distributed at a Montgomery, Ala., antiabortion rally sponsored by the group Operation Rescue, according to an Associated Press report.
Five months after Gunn's slaying, Tiller was shot in both arms outside his Wichita clinic by a woman who had praised Gunn's killer as a hero.
In response, Congress passed the Freedom of Access to Clinic Entrances Act, which President Clinton signed in May 1994. The law outlawed "force, threat of force or physical obstruction" to patients and clinic workers.
Supporters of abortion rights credit the law with stemming some of the intimidation at clinics. But serious incidents continued throughout Clinton's presidency, which was viewed as inhospitable to the antiabortion cause.
In July 1994, Paul Hill, a former Presbyterian minister, shot and killed Dr. John Britton and a 74-year-old clinic escort in Pensacola. In December of that year, John Salvi III shot up two Boston-area clinics, killing two receptionists and injuring five other people.
In January 1998, a bomb planted at a Birmingham, Ala., clinic killed a security guard and injured a nurse. The culprit, Eric Rudolph, a foe of gay rights and abortion, had also carried out a bombing at the 1996 Olympics in Atlanta, which killed one and injured more than 100.
Rudolph disappeared into the mountains of Appalachia. He became the subject of a protracted manhunt and, in some circles, a folk hero. He was not captured until 2003. He pleaded guilty to a string of bombings and was sentenced to life in prison.
Until Tiller's slaying Sunday, the last known slaying of an abortion provider was in October 1998, when obstetrician Barnett Slepian was killed by James Kopp in Amherst, N.Y. Kopp was convicted of murder in 2003 and sentenced to 25 years to life.
Less lethal tactics have included the release of foul-smelling butyric acid at clinics. In 2001, when the nation was gripped with fear stemming from legitimate anthrax threats, more than 500 clinics received letters with fake anthrax, according to NARAL Pro-Choice America.
Those who support abortion rights maintain that violence and the threat of violence have led to a shortage of abortion providers. According to NARAL, 87% of U.S. counties lack an abortion provider.