Judge Enters Not Guilty Pleas For 13-Year-Old Girls Accused of Stabbing Classmate to Impress 'Slender Man'

Morgan Geyser and Anissa Weier were 12 at the time of the brutal attack in Waukesha, Wisconsin last year but they are being tried as adults.

A judge has entered not guilty pleas for two 13-year-old girls accused of luring a classmate into the woods before stabbing her 19 times as a sacrifice to the fictitious character "Slender Man."

Morgan Geyser and Anissa Weier were 12 at the time of the brutal attack in Waukesha, Wisconsin last year but they are being tried as adults. They face decades behind bars if they're convicted.

On Friday, a judge entered not guilty pleas for both of the girls after their lawyers refused to do so. They will be tried together in October.

After the hearing, attorneys for the girls said by not entering a plea, they were objecting to the court’s jurisdiction and were hoping the case could be moved to juvenile court.

Read: Slender Man Stabbing: Two 12-Year-Olds Accused of Stabbing Friend To Please Mythical Entity

The duo lured Payton Leutner into the woods after a sleepover in May 2014 before trying to kill her, investigators claim.

Police say the girls wanted to win favor with Slender Man, a mythical horror character. They thought they would go and live with him in his mansion if they carried out the attack, police documents say.

Authorities say Geyser told police their plan to kill their friend began as early as December 2013.

The young girl was stabbed 19 times but she managed to crawl into a road, where a passing cyclist found her and called for help. She was rushed to hospital, where she recovered, and returned to school three months later.

Geyser and Weier, who have been in custody since the day of the attack, each face a charge of attempted first-degree intentional homicide.

Read: Slender Man Stabbings: Suspect Sacrificed Barbies, Drew Dead Children, Wrote 'I Love Killing People'

They face 65 years in prison if convicted as adults.

Slender Man is a fictitious character who is described as an unnaturally tall and thin man who wears a dark suit and has no visible facial features.

Dexter Morgenstern, who has written a self-published novel about Slender Man, previously told INSIDE EDITION: "Slender Man is sort of a popular urban legend. People have created web shows. People have created their own photos, their own stories. They've created a whole universe about the Slender Man."

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