In the months before a gunman entered a Planned Parenthood clinic in Colorado Springs Friday afternoon, the staff there had been experiencing even more scrutiny and angry criticism than usual.

Both police and Planned Parenthood of the Rocky Mountains have said they do not know what motivated the gunman. Three people, including a police officer, died after a five-hour violent standoff. Nine others were injured. The group’s CEO, Vicki Cowart, said Friday night that all staff was accounted for. But the gunman chose a location for his deadly assault that was already on high alert.

Abortion clinics are used to being targets – indeed, the clinic reportedly had a safe room with bulletproof vests – but this year has been different. Last summer, Planned Parenthood of the Rocky Mountains’ medical director was one of several abortion providers featured in anti-abortion sting videos, accusing them of breaking laws regulating the donation of fetal tissue for medical research. Conservative activists and legislators, most prominently Colorado Springs’ own elected officials, have been condemning the group for months, accusing it of trafficking in “baby parts.”

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Planned Parenthood, both nationally and in Colorado, has denied any wrongdoing, and investigations in eight states have cleared the group. In August, Colorado’s Republican attorney general, Cynthia Coffman, announced there were no plans to investigate Planned Parenthood over the videos, deferring to a decision from the Colorado Department of Public Health and Environment.

Several Republican legislators were outraged, including in Colorado Springs, which was once nicknamed the “evangelical Vatican” for its high concentration of prominent churches. State Rep. Dan Nordberg, who represents Colorado Springs, declared, “A civilized society cannot allow unethical and illegal medical practices such as the harvesting of aborted human organs and babies for monetary gain. I would hope that even proponents of abortion would agree to that much.” And Rep. Doug Lamborn, who represents Colorado Springs in the U.S. Congress, said then, “It is shocking that despite Colorado being the epicenter of a national outcry over the trafficking of aborted baby body parts for profit, our state officials, who have been entrusted with the responsibility to ensure compliance with state law, have chosen to relinquish their duty.”

The target of their ire: Savita Ginde, Planned Parenthood of the Rocky Mountains’ vice president and medical director, who was secretly recorded by anti-abortion activists known as the Center for Medical Progress at the Denver clinic. CMP claimed the video showed Ginde “negotiating a fetal body parts deal, agreeing multiple times to illicit pricing per body part harvested, and suggesting ways to avoid legal consequences.”

Under the law, abortion providers can be reimbursed for processing time and storage of fetal tissue their patients voluntarily donate. Ginde is shown on the video saying she thinks a per-specimen reimbursement is preferable to a flat fee.

Planned Parenthood of the Rocky Mountain’s CEO Cowart said at the time, “The accuracy of today’s heavily edited video cannot be confirmed and the full length footage that would put any comments in context has not been made available. To be clear, however, we are certain that no laws were broken and that accusations made by those who oppose Planned Parenthood’s mission and services are false.”

A MediaMatters analysis of the longer footage released pointed out that another clinic employee says in the video that fetal tissue donation is “so small, compared to the other services we offer,” adding, “I oversee all research in PPRM and all affiliates and everything, so it’s something that could easily be cut budget wise, from a numbers perspective.”

The state has long been fiercely divided over over abortion. It is the headquarters of the personhood movement, which advocates for amending state constitutions to recognize fertilized eggs as persons. The socially conservative group Focus on the Family, whose founder condemned Barack Obama as “the abortion president,” has its headquarters in Colorado Springs. At the same time, Colorado has some of the least restrictive abortion laws in the country; Dr. Warren Hern, one of a handful of providers of third-trimester abortions who speaks publicly about his work, practices in Boulder. During Colorado’s most recent U.S. Senate race last year, incumbent Mark Udall was disparagingly nicknamed “Senator Uterus” for repeatedly pointing out his opponent Cory Gardner’s fervent opposition to abortion rights – including campaigning for personhood. Gardner won, even as personhood lost for a third time.

CBS News reported in September that a new FBI Intelligence Assessment noted that ”it is likely criminal or suspicious incidents will continue to be directed against reproductive health care providers, their staff and facilities,” following the release of the videos.

“The fear is an everyday thing,” David S. Cohen, a law professor and co-author of “Living in the Crosshairs: The Untold Stories of Anti-Abortion Terrorism,“ told MSNBC. He added, “Colorado is home to some of the most extreme members of the anti-abortion movement,” such that in 2000, the Supreme Court upheld an eight-foot bubble zone around patients entering abortion clinics, a precedent it declined to overrule in 2014.

Anti-abortion activists, argued Cohen, “have a right to criticize abortion providers. They do not have a right to defame or misrepresent themselves … To falsely accuse an entire entity of selling baby parts is the kind of rhetoric that encourages this kind of behavior.”

On Friday, as news of the attack emerged, David Daleiden, the young anti-abortion activist behind the videos, told the conservative site Breitbart that his group “does not support vigilante violence against abortion providers.” He added, “We only visited the Denver clinic in Colorado.”