Charles Manson Follower Patricia Krenwinkel's Parole Blocked by California Gov. Gavin Newsom

California Gov. Gavin Newsom blocked the parole of cult leader Charles Manson's 74-year-old follower Patricia Krenwinkel, multiple outlets confirmed.

On Friday, Newsom, 55, overruled the recommendation for her release after citing the inmate "still poses an unreasonable danger to society if paroled at this time," the Los Angeles Times reported, adding that the ruling marked her 15th-time parole was unsuccessful.

"Ms. Krenwinkel fully accepted Mr. Manson's racist, apocalyptical ideologies," Newsom said, per The Associated Press. "Ms. Krenwinkel was not only a victim of Mr. Manson's abuse. She was also a significant contributor to the violence and tragedy that became the Manson Family's legacy."

In his decision, which came months after the state Board of Parole Hearings recommended Krenwinkel's release in May, Newsom acknowledged Krenwinkel's completion of rehabilitation and education programs during her time behind the bar, noting she has "demonstrated effusive remorse."

However, according to the AP, Newsom believed "her efforts have not sufficiently reduced her risk for future dangerousness" nor did she have "sufficient insight" into what prompted her to take part in the murders.

"Beyond the brutal murders she committed, she played a leadership role in the cult and an enforcer of Mr. Manson's tyranny. She forced the other women in the cult to obey Mr. Manson, and prevented them from escaping when they tried to leave," he explained, per the outlet.

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For two nights in August 1969 in Los Angeles, Manson instructed a handful of his followers — including Krenwinkel, Tex Watson, Susan Atkins, and Leslie Van Houten — to kill nine people. Linda Kasabian, another Manson follower, became the state's key witness and was granted immunity in exchange for her testimony.

In 1971, Krenwinkel was convicted of seven counts of first-degree murder and received a death sentence. A jury found her guilty of killing actress Sharon Tate Polanski, Abigail Ann Folger, Wojciech Frykowski, Steven Earl Parent, Jay Sebring, Leno, and Rosemary La Bianca.

Her sentence was later reduced to life in prison with the possibility of parole after the California Supreme Court decided the death penalty was unconstitutional in 1972.

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After fellow Manson follower and convicted murderer Atkins died in prison in 2009, Krenwinkel became the longest-serving female inmate in California.

Representatives for Newsom's office and Krenwinkel's lawyer, Keith Wattley, did not immediately return PEOPLE's request for comment.

Manson died in prison in November 2017.