Prosecutors in southeastern Wisconsin say two 12-year-old girls stabbed their 12-year-old friend nearly to death to please a mythological creature called 'Slender Man' they learned about on Facebook.

The victim was lured into the woods near Waukesha, Wisconsin and stabbed 19 times with a kitchen knife.  She managed to crawl to the roadside where she was aided by a passing bicyclist.  Many of the victim's organs were stabbed, but one cut narrowly missed a major artery near her heart.

Who is 'Slender Man'?

One of the girls told police they were trying to become "proxies" of Slender Man, a mythological demon-like character they learned about on creepypasta.wikia.com, a website about horror stories and legends, and prove his existence. After killing their friend the pre-teens planned to run away to the 'demon's forest mansion', the complaint said.

The other girl confessed to a detective she sees Slender Man in her dreams, that he watches her and can read her mind and teleport.

Both girls, who are under arrest and expected to be formally charged as adults with first degree, premeditated murder, reportedly told investigators they had been planning the slaying since December 2013, according to abc15.com.

The accused, now in custody, seem to be cooperating with authorities.