WICHITA, Kan. (AP) — An anti-abortion activist who shot and wounded a Kansas abortion doctor and firebombed clinics in Oregon and other states in the 1990s was released Tuesday from federal prison to a halfway house to finish her sentence, sparking fears for the safety of abortion clinic workers.

The Federal Correctional Institution in Waseca, Minnesota confirmed Rachelle "Shelley" Shannon has been released, and sent to a halfway house where she will finish a 20-year sentence related to two Oregon cases of arson and other crimes targeting abortion clinics. Her final release date is Nov. 7.

Vicki Saporta, president of the National Abortion Federation, said she is alerting affiliated abortion clinics that Shannon is now out of prison.

"This is someone who not only committed multiple acts of violence herself, but also encouraged others to murder abortion providers," Saporta said. "She has shown zero remorse."

Shannon had earlier completed an 11-year sentence for the 1993 shooting of abortion provider George Tiller in Wichita.

Tiller had been the target of relentless protests for most of the 36 years that he performed abortions at his Wichita clinic, where he practiced as one of the nation's few providers of late-term abortions. His clinic was bombed in 1986 and he was shot in both arms by Shannon in 1993.

On May 31, 2009, Tiller was shot and killed at his church by Scott Roeder, an anti-abortion extremist who had admired Shannon. Roeder testified during his murder trial that he visited Shannon when she was imprisoned in Topeka.

On the eve of Roeder's murder trial for killing Tiller, Shannon sent a message through the prison email system to another anti-abortion activist in Iowa in which she wrote that Tiller "needed to be killed for the sake of justice."

Tiller's building was purchased by Trust Women, which now operates a clinic in it offering abortion and other reproductive health care services. Julie Burkhart, the founder and chief executive officer for Trust Women, said Shannon's release raises concerns about the safety of their workers.

"It raises some red flags and makes me think more about security and safety," Burkhart said, adding she wants to make sure people who work there are not in harm's way.

Burkhart, who once worked for Tiller, said that hearing the news that Shannon was out of federal prison "dredged up a lot of old memories and feelings and it has been much more emotional than I anticipated."

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Associated Press Writer David Crary in New York contributed to this report.

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