Slenderman attacker: 'We were trying to kill her'

One of two 12-year-old girls who repeatedly stabbed a Wisconsin classmate in the so-called Slenderman attack told investigators "we were trying to kill her" in the hours after the attack.

Morgan Geyser and Anissa Weier brutally attacked Payton Leutner in the woods in the Milwaukee area in May of 2014. Investigators say Geyser stabbed Leutner 19 times while Weier urged her on.

"What were you trying to do with her when you stabbed her?" a detective asked Geyser in the aftermath, according to video obtained by ABC News and People.

"Kill her," Geyser responded. "I might as well just say it. We were trying to kill her."

Geyser's mother told ABC News that she was shocked by her daughter's lack of remorse during the interview.

"The interrogation is very difficult to watch because that’s not my daughter saying those things," Angie Geyser told ABC News. "That’s not the way that she speaks, that’s not the way that she acts."

The teen suspects said the attack on Leutner was an effort to satisfy the fictional horror character Slenderman.

Leutner, who was also 12, survived the attack by crawling out of woods, and she was found by a passing bicyclist.

Geyser agreed to plead guilty to attempted first-degree intentional homicide to avoid prison, and will continue treatment in a mental hospital. A judge will rule on how long she will be committed later this week, according to ABC News.

Weier was sentenced to 25 years in a mental hospital.

With News Wire Services