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AUSTIN, Texas - Court paperwork reveals more information about a teenager's plan to shoot up an elementary school.
Giana Castillo, 17, is charged with terroristic threat. She's accused of planning an attack on Graham Elementary, which she previously attended.
Yaremy Lopez, a Graham Elementary parent, shared her reaction.
"I grew up in this school and I would never expect it to happen in my childhood school," she said. "I'm very unhappy with it, I don't feel safe."
Giana Castillo
Authorities say a tipster saw Castillo's post on Instagram about planning an active shooter event and idolizing past shooters. Investigators traced the IP address.
The arrest affidavit shows posts of weapons she wanted to buy, plus images on her phone that say she "always had a sort of hatred for humanity."
The paperwork also showed conversations with another person planning how to get weapons and when to carry out the attack.
RELATED: Teen charged with terroristic threat for allegedly making 'concerning' Instagram posts
Dr. Kathy Martinez-Prather, director of the Texas School Safety Center and Texas State University, emphasizes the importance of speaking up if you see or hear something suspicious.
"These violent events can be prevented because the acts are typically planned in advance. This isn't just one day someone wakes up and decides to do this. Individuals typically tell others beforehand about their plans," she said.
Since 2019, every Texas school district has been required to make a school behavior threat assessment team available.
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"The idea here is we want to identify those concerning behaviors well before individuals get on a pathway to violence," Martinez-Prather said.
She says there's no profile for school attackers.
"We can go back to case studies and research over the years in which averted school plot attacks where students were often motivated by a grievance that they had with another classmate, school attackers or attackers in general generally are feeling despondent or despair, may even be suicidal," she said.
She commends law enforcement and the people who spoke up for their quick action.
"In this situation, a terrible tragedy was avoided," she said.
"Security here has been better as well, so I do feel a little bit more secure, but what parent would like to know that their child's school was threatened," Lopez said.
AISD police have added more patrols to Graham Elementary since the threat.