A Pennsylvania woman who called herself “Jihad Jane” online and plotted to kill a Swedish artist was sentenced in federal court Monday to 10 years in prison after telling a judge she was once obsessed with Islamist jihad.

Colleen LaRose had faced a potential life term. But Chief Judge Petrese B. Tucker of the U.S. District Court in Philadelphia accepted a government request to reduce the sentence, because of LaRose’s extensive cooperation with investigators.

Prosecutors still asked for decades in prison, fearing she remains dangerous.

LaRose, 50, of Pennsburg, Pa., told the judge she once had thought constantly about becoming a martyr for an Islamist cause, describing herself as being “in a trance.”

“I don’t want to be into jihad no more,” she said.

She was sentenced to 10 years in prison plus five years of supervised release. She could be out in a little over four years, given the more than four years she has already served and the potential for time off for good behavior.

Prosecutors depicted LaRose as a “lonely and isolated” woman who sought excitement by joining the jihadist cause.

Federal investigators say she participated in a 2009 conspiracy to target artist Lars Vilks because of his series of drawings depicting the prophet Muhammad as a dog.

The Justice Department said Ali Charaf Damache, an Algerian who was living in Ireland, recruited LaRose and another U.S. woman via jihadist Web sites.

LaRose left the terrorist cell in Ireland after about six weeks, Assistant U.S. Attorney Jennifer Arbittier Williams said Monday, not because she thought better of the murder plot but because she “grew frustrated because her co-conspirators were not ready for action.”

Others need to know, Williams said, that “if you plot to kill someone, you are going to receive decades behind bars — decades — even if you cooperate.”

LaRose returned to Philadelphia in 2009 to surrender.

Public defender Mark Wilson said that LaRose has come to understand the true, peaceful tenets of Islam and that “there’s virtually no chance that she would ever be involved in violent jihad ever again.”

Vilks told the Associated Press that he understands that tough sentences can act as deterrents but that he felt LaRose’s term was too harsh.

“To lock her up for so many years seems like overkill to me,” Vilks said. “This is a person who has been through a lot of difficulties in her life and needs mental care more than anything else.”

Vilks said that he is still under threat but that he has around-the-clock protection that makes him feel safe.