A 14-year-old was booked into juvenile detention on investigation of six felony charges in connection with threats made Wednesday toward three Snohomish County schools.

Snohomish County Sheriff’s Office deputies responded to a threat made toward the three Mukilteo School District schools on Wednesday morning and discovered an anonymous social media post that threatened violence, according to the Sheriff’s Office.

The post “indicated there would be a shooting at Voyager Middle School, Explorer Middle School and Mariner High School,” the Sheriff’s Office said in an emailed statement.

Detectives were able to identify the source of the social media post and deputies responded to the suspect’s residence, according to the Sheriff’s Office.

The Sheriff’s Office did not immediately respond to a request for more information about the 14-year-old, including whether the teen was a student at any of the threatened schools.

The threat prompted an elevated police presence at the schools Thursday. The principal of Explorer sent a letter to parents, Q13 Fox News reported, notifying them the school was working with law enforcement, the district and staff to ensure the schools are safe.