Brooke Higgins and Sienna Johnson, both 16, have been charged with conspiracy to commit first-degree murder under extreme indifference and conspiracy to commit first-degree murder after deliberation, 9 News reports. The two girls were thwarted before executing a Columbine-style attack they'd allegedly planned on Mountain Vista High School in Castle Rock, Colorado.

According to Westword, both Higgins and Johnson are being charged as adults. In a court hearing yesterday, prosecutors said the girls had a "fascination" with the 1999 Columbine shooting, and that Johnson had written in her diary that Higgins was "someone who's got what it takes" to execute such an attack and that together they'd be "unstoppable" in making school "a living f*cking nightmare."

ABC 7 reports Higgins allegedly used her phone to research female mass shooters and whether or not minors could purchase guns at gun shows. The defense argued having a fascination with guns and Columbine is not a crime: "This is a thought crime, at best," Higgins's lawyer said.

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Brooke Higgins is second teen charged as an adult in Mountain Vista H.S. murder plot - https://t.co/DGL0IbUoCQ pic.twitter.com/rwSrjtKYqa — Denver7 News (@DenverChannel) January 14, 2016

The same lawyer is looking to distance his client from Johnson, maintaining the two girls were merely acquaintances and that Johnson, who has allegedly brought a BB gun to school before and harmed pets in the past, was the driving force behind the plan.

ABC 7 also reports the girls' high school was notified of the threat via a texting tip line on Dec. 12 and they were arrested immediately after. The exact nature of the alleged plan has not been revealed, but prosecutors said Johnson was found with a detailed map of where everyone in the school would be at that time. She'd also allegedly texted a friend saying she'd warn her before the attack so she'd know not to come to school.

Both Higgins and Johnson's bonds are set at $1 million and they will remain in jail until their trials begin later this year, CBS Denver reports. They have undergone and are scheduled to undergo more psychological evaluation.

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Tess Koman Senior Editor Tess Koman covers breaking (food) news, opinion pieces, and features on larger happenings in the food world.

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