Two civilians and a police officer were killed when a gunman opened fire at a Colorado Planned Parenthood clinic in a nearly six-hour standoff on November 27, 2015.
Planned Parenthood is a healthcare non-profit-making group with 59 affiliates and 700 clinics around the United States and the largest single provider of abortion.
Planned Parenthood dates back to 1916 when social activist and nurse Margaret Sanger opened the first birth control and family planning centre in Brooklyn, New York.
The group says each year 2.7 million people in the US visit its health centers for health care services and information. Abortion is among the services Planned Parenthood clinics provide, an issue that’s made the organization a target in the past.
Planned Parenthood has faced sharp criticism in Washington and from some Republican presidential candidates on the campaign trail after an anti-abortion group released a series of videos alleging that the family planning clinic engaged in the selling of fetal organs and parts for profit.
The clinic has strongly disputed the videos and contended the tapes provide a distorted account because they are heavily edited.
At least three Planned Parenthood buildings have been vandalized since September.
In 2014, abortion providers in the United States saw 12 incidents of vandalism, one burglary, one invasion, one arson attack, one death threat and four stalking incidents, according to the National Abortion Federation.
In the 1960s and 1970s, Planned Parenthood affiliates were at the fore of many court fights to make abortion legal.