CEDAR PARK, Texas (KXAN) — A 17 year old is facing a felony charge of false alarm or report after a fake threat was made against Vista Ridge High School, according to an affidavit.

According to the Cedar Park Police Department, a threat of a mass shooting at Vista Ridge was reported last Tuesday by two students, Abbygayle Harris and another student. Police said the threat came from an anonymous Snapchat account.

Police said Harris and the other student reported after they left the office from reporting the threat, they both got a text message from an unknown number that said the sender knew the two had reported the threat. The message also said the sender was going to “shoot up the school at approximately 3 p.m.”

Police ran the phone number the text came from and identified the number as belonging to a TextNow account. TextNow is an app that can turn any wifi connected device into a phone with its own phone number, according to Smart Social.

Leander ISD’s security director told Cedar Park Police Harris was known to the department and had in the past made false reports of immediate threats to schools.

Cedar Park officers then went to Vista Ridge High School to meet with Harris, who admitted to sending the threatening messages to herself and reporting them to the school resource officer and administration.

Harris said her friend wanted to skip school and was the one who sent the initial Snapchat message, but Harris had the idea of sending the “anonymous message” to herself and her friend.

Harris was arrested on Friday by the Cedar Park Police Department.