An empty shell casing was discovered Wednesday on the grounds of Lehighton Area High School, district officials said, prompting action from school authorities.

The district released a statement to parents that detailed the incident and reinforced student safety as a top priority.

The casing was found during routine activities on campus, district officials said, which led to precautionary measures.

“Upon discovery of the shell casing, the following steps were immediately taken and the area was secured to ensure the safety of all students and staff,” the statement said. “A working lockdown occurred, and the area was searched.”

District police and administrators responded promptly, the statement added. “At this time, we have no reason to believe there is any threat to the safety of our school community,” the statement said. “We understand that incidents like this can cause concerns. If you have any questions or concerns, please do not hesitate to contact the administration at the high school.”