Three people, including at least one student, were taken into custody at Central Connecticut State University on Monday after a security scare and lockdown that campus police said may have been caused by a student in a Halloween costume carrying a sword.
University officials placed the school on lockdown for several hours after campus police received calls about a suspicious person.
The investigators quickly traced the incident to a dormitory building where video footage showed the person entering shortly after the 911 calls.
"No weapons recovered, right now what we're doing is going back into the room to search," Chris Cervoni, chief of the campus police force, told reporters on Monday after the incident's conclusion. He said police received calls about a person who appeared to be carrying a sword and possibly a gun, but Cervoni allowed it "possibly could have been a Halloween costume."
No one was injured in the incident.
Cervoni added that campus officials are not treating the incident as a prank. "It wasn't a prank because there was concern, there was alarm," he said.
Central Connecticut State University is located in New Britain, outside Hartford.
U.S. schools have been on a heightened alert in recent years following a string of shooting incidents including an attack on an elementary school in Newtown, Connecticut, last December in which a gunman killed 20 young children and six adults.
(Additional reporting by Richard Valdmanis; Editing by Dan Grebler, Nick Zieminski and Jeffrey Benkoe)