BATON ROUGE - Reports of an 'armed intruder' stirred up concern on LSU's campus Tuesday afternoon.

The alert went out around 3 p.m. warning students to stay away from Coates Hall. It included a message telling people to "run, hide or fight," a saying used by many universities nationwide during potentially dangerous situations on campus.

Run: Exit the area and move away from danger.
Hide: If escape is not possible, find a safe area to hide.
Fight: This is an absolute last resort.https://t.co/Ow23ySe5gB

— LSU (@LSU) August 20, 2019

No injuries were reported.

A witness who was inside the building said a member of the cleaning crew said they thought they saw someone with a gun and staff reported it to police. An LSU spokesperson says the scare may have been caused by a police officer in plain clothes walking around with a gun on his belt.

The attorney general's office released a statement Wednesday suggesting that the person mistaken for an intruder may have been one of its officers there to teach a safety course.

The officer was invited by LSU's Women Center as part of the 'Engage.Lead.Geaux' event focused on social media responsibility. 

Police found no threat on campus, and the school resumed normal operation Tuesday afternoon.