Colleen LaRose, 50, was scheduled to be sentenced Monday, the Philadelphia Inquirer reported. She pleaded guilty in 2011 to providing material support to terrorists, a crime that could bring her life in prison.
LaRose was recruited online by al-Qaida in 2009 and given the assignment of killing Lars Vilks, a Swedish cartoonist who had drawn Muhammad's head on a dog's body, investigators said.
Federal prosecutors Jennifer Arbittier Williams and Matthew F. Blue, in a court filing, asked a judge to give LaRose a sentence of several decades. They urged the court to "send a strong message to other lonely, vulnerable people who might be enticed by online extremists promising fame and honor."
While LaRose began cooperating "diligently, candidly, and tirelessly" after her arrest, she appeared proud of her association with al-Qaida, prosecutors said.
"LaRose seemed to take pleasure and even pride recounting her glory days as 'the hunter,'" Williams wrote. "Her demeanor continued to grow wistful -- despite the passage of time -- when speaking with government agents about some of her co-conspirators and their plans."
Prosecutors conceded LaRose, a native of Texas, had had a difficult life with a childhood of abuse and neglect, an early marriage and divorce and a string of convictions for offenses that included bad checks and criminal trespass. In 2002, she moved to Pennsburg, Pa., where she was described as being bored and lonely, with a boyfriend who was often away.