Investigators said Julie Franck and an accomplice wore ski masks Oct. 9 when they robbed Franck's mother of the ring and the second suspect used a Taser on the victim about 15 times, the Chicago Sun-Times reported Monday.
Police said Franck, who fled in a Smart car, was recognized when a witness pulled off her mask.
Franck, 36, who also allegedly stole $200 cash and credit and debit cards from her mother, was arrested Friday on an armed robbery charge and jailed in lieu of $300,000 bail.
It was unclear whether the second suspect was arrested.
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