(CNN) A US prosecutor said Tuesday that a teenage girl who allegedly plotted to kill her best friend also shared child pornography videos of other victims with her co-conspirator.

Denali Brehmer, an 18-year-old from Anchorage, Alaska, has been indicted in federal court on charges of conspiracy, production and distribution of child pornography, and will face first-degree murder and other counts in state court.

Brehmer is accused of luring Cynthia Hoffman, 19, on a hike June 2 and shooting her in the back of the head.

Authorities say she plotted online and by text with Darin Schilmiller, 21, who court documents say is from New Salisbury, Indiana. He allegedly posed online as a millionaire named "Tyler," and offered Brehmer at least $9 million to kill Hoffman and send him "videos and photographs of the murder," according to the Alaska Department of Law.

Federal court documents allege Schilmiller had also directed Brehmer to sexually assault an "8- or 9-year-old" and a 15-year-old and send videos to him. Brehmer told investigators she did, and video of the 15-year-old was recovered by investigators.

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