(CHESTER, PA) – A Chester High School student is in custody following an online threat that was posted on Instagram Tuesday. The post threatened an attack against students in schools in the Chester-Upland School District, Chester Community Charter School and Chichester High School.

The threat was posted shortly before 7:00 pm on Tuesday. Chester authorities were immediately notified. An investigation utilizing resources from the FBI, Chester, Chichester and neighboring towns was conducted and subsequently, a 17-year-old female student was taken into custody.

All schools within the Chester-Upland School District are expected to open Wednesday morning.

The Chester Police department will issue a press release further detailing the investigation.