ROCK HILL — A tip from an anonymous source led school officials and police to a teenage York Preparatory Academy student accused of bringing marijuana to school on Monday.

A school official received the tip that a 13-year-old girl had pot on school grounds, according to a Rock Hill Police report. The administrator confronted the student, who admitted to having a small amount.

Officials measured the drugs at 2.71 grams, the report states. An officer took the marijuana and petitioned the girl to family court for a drug law violation.

According to the charter school’s student/parent handbook, having drugs on school property is a “Class III offense” punishable by expulsion.