"At approximately 9:15 a.m., a kindergarten student experienced a mental health crisis," said Chester Upland School District officials in a statement.
"Unfortunately, the incident resulted in three students sustaining minor injuries from a pencil held by the student in crisis."
Administrators said the three were immediately evaluated and treated by the school nurse. EMS and police were also called "to help deescalate the situation," the district said.
The injured three were turned over to their parents and the student in crisis was removed from school and sent home, officials said.
"Subsequent disciplinary action will be evaluated and assessed according to CUSD's protocol," wrote interim Superintendent Latrice M. Mumin.
"CUSD understands the unsettling nature of this incident and is dedicated to providing support to all those affected."
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