WASHINGTON, D.C. (CBSDC/AP) — D.C. Police and school officials said American University’s campus was on lockdown for 85 minutes after police received calls of a man with a gun on campus Wednesday night.

Camille Lepre, the American University assistant vice president of communication says the campus first received the report from a student spotting the man on an American University shuttle bus with what they believed to be a gun.

The university sent out tweets saying they were on lockdown at about 7:40 p.m. American University and D.C. police were investigating the area, but spokesman Officer Hugh Carew said officers never confirmed the report of a gunman on campus.

D.C. Police Department’s Lt. Jesse Porter said authorities later determined the man was an off-duty police officer and the lockdown was lifted. Porter said no weapon was ever displayed, no threats were made, no crime was committed and there were no arrests or injuries.

Earlier authorities were urging students to seek shelter and stay indoors.

The campus later tweeted out around 9:20 p.m. that the lockdown was lifted and were going to resume normal operations.

“American University thanks the entire AU community for their cooperation during this incident. Every student is safe tonight. In this case, someone saw something and said something. The system worked,” said Lepre.

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