A teenager has been charged with a third-degree felony for allegedly threatening violence at Graham Elementary School.
KXAN was first to report the arrest Friday.
Giana Castillo, 17, was taken into custody Tuesday and charged with one count of making a terroristic threat. Seventeen-year-olds can be tried as adults in Texas.
Castillo's parents are cooperating with law enforcement, according to a joint statement from the Austin Police Department, Austin ISD and the FBI.
"Thanks to the partnership with APD, the FBI, and AISD PD, a possible tragedy was prevented and our community remains safe," the statement read. "This case is a testament to the importance of staying vigilant and reporting suspicious behavior, both in person and online."
The statement said the FBI got a tip about an Instagram user "making concerning statements online."
The FBI contacted the Austin ISD police department late Tuesday about the alleged threat, according to a letter the school's principal sent to families.
"The FBI had already located the suspect and made the arrest before the start of our school day," Principal Bardo Montelongo wrote.
Montelongo noted that although law enforcement "have no reason to believe that there is an existing threat" to the school, Austin ISD police had increased its presence on campus.
In a second letter to families Friday, Montelongo underscored the school's commitment to keeping students safe.
"While we understand that there were plans to cause harm, our local law enforcement was able to intervene swiftly before any plans could more fully develop," he wrote.
The school is holding a meeting for families Monday to review safety protocols and provide mental health support. It is not open to the public.
"We’re committed to keeping our community safe and have taken measures to prevent any threats," Austin ISD Police Chief Wayne Sneed said in a statement.
He added that the AISD police department is currently recruiting officers to comply with a 2023 Texas law requiring districts to have an officer at every campus during regular school hours.
This story is developing.
