WASHINGTON — Authorities have announced that a Wisconsin woman, previously convicted in the notorious 2014 “Slender Man” stabbing case, is now missing after she removed her monitoring bracelet and left a group home.

The Madison Police Department has identified the missing person as 22-year-old Morgan Geyser, who was last spotted at about 8 p.m. on Saturday near Kroncke Drive. She was with an adult companion when she detached her Department of Corrections monitoring device and left. Police have circulated a recent surveillance image and are urging anyone with information to contact 911 immediately.

On Sunday, Geyser’s attorney, Tony Cotton, expressed his concerns, stating that he is unaware of the specifics regarding her disappearance and is calling for her to surrender herself.

“For her own benefit, I strongly advise her to turn herself in promptly and avoid further complications,” Cotton stated in an Instagram video, at times speaking directly to Geyser. “We are currently unaware of the details surrounding her actions or if anyone may have helped her.”

Geyser had been residing in a closely monitored group home after being released earlier this year from the Winnebago Mental Health Institute, where she had been institutionalized for seven years. Her release was granted following expert testimony confirming her substantial mental health improvements, as reported by CBS News.

The Madison Police Department said Sunday that it was not made aware that Geyser was missing until nearly 12 hours after she left the group home. The state Department of Corrections received an alert Saturday night that Geyser’s ankle monitor had malfunctioned. The department contacted the group home where she lived about two hours later and was told she was not there and had removed the bracelet, Madison police said.

The Department of Corrections issued an apprehension request just after midnight. The Madison Police Department said it did not learn Geyser was missing until someone from the group home called the next morning. The corrections department did not immediately respond to an email seeking comment.

Geyser and her friend, Anissa Weier, were 12 years old when they lured classmate Payton Leutner into a Waukesha park during a sleepover in 2014. Prosecutors said Geyser stabbed Leutner 19 times while Weier encouraged her. The girls told investigators they believed they needed to kill Leutner to appease the fictional horror character Slender Man.

Leutner survived her injuries, and Geyser pleaded guilty to attempted first-degree intentional homicide in 2017. She was ordered committed to a psychiatric hospital for up to 40 years in 2018 after arguing she was not responsible due to mental illness.

Weier, who pleaded guilty to a lesser charge, was committed for 25 years but granted release in 2021 under GPS monitoring and supervision.

The Associated Press contributed to this report.