A teenage girl is in police custody after she allegedly posted online threats against several schools in Chester, Pennsylvania, ABC Philly reported.RELATED:Pa. launches first-ever 'Teen Health Week' spearheaded by local teenThe unidentified 17-year-old girl allegedly posted threats on Instagram against Chester Upland School District, Chester Community Charter School and Chichester High School.RELATED:Pregnantteendies after shoveling“I’m coming tomorrow shooting up every Chester Upland School District school Chester Community Charter School (both) and Chichester High School as well,” she wrote in all caps with emoji sprinkled about. “All blacks must die!”RELATED:Friend testifies Pennsylvaniateenplotted murder after mom tried to end romancePolice reportedly traced the message to a home on Harshaw Road where they found the teen at a sleepover. She admitted to making the threat and was placed into custody.All of the threatened schools will remain in session.Matt Lee is a Web producer for Metro New York. He writes about almost everything and anything. Talk to him (or yell at him) on Twitter so he doesn’t feel lonely@mattlee2669.