Police learned the Mount Pleasant High School student found the pills at his grandmother's home where his late grandfather used to live.
The juvenile is charged with two counts of assault, reckless endangering and drug charges.
One of the two hospitalized teens is still in the intensive care unit at A.I. Hospital for Children. Both had serious medical complications after paramedics were called to care for a 17-year-old having a drug-induced seizure.
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