WAUKESHA, Wis. (AP) — The judge in the case of two girls accused of stabbing a classmate as a sacrifice to a fictitious horror character called Slender Man has said the girls will be tried together and set a trial date of October 15th.

Judge Michael Bohren decided previously that the case should be tried in adult court, and the 13-year-old girls face decades in prison if convicted.

Investigators say they plotted to lure Payton Leutner into the woods after a sleepover in suburban Milwaukee. They say the girls intended to kill their friend to earn a place in the mansion of Slender Man, a character described as unnaturally tall and thin with no visible facial features.

Slender Man stories have proliferated online in recent years.

The Associated Press is not identifying the girls because their case could land on appeal in juvenile court, where proceedings are closed to the public.

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