The South Texas ISD Preparatory Academy was placed on lockdown Friday morning, according to a news release from the city of Edinburg.

The Edinburg Police Department received a call in reference to the lockdown on campus — located at 724 S. Sugar Rd. — shortly before 10 a.m., the news release stated.

A news release from the city said the lockdown was prompted after a student found ammunition in one of the boy's bathroom stalls.

Six 9 mm bullets were recovered, the release stated. A search of the campus yielded no weapons or any other ammunition.

The lockdown was lifted at around 2 p.m. 

The Edinburg PD Juvenile Investigations Divisions is investigating the incident, and are interviewing several students.