NEW HAVEN - A tense day stretched into the evening hours at Yale University in New Haven after a report of a gunman on campus put police on high alert, but authorities now say that the report was unfounded.

Chopper 12 was above the campus after reports of a potential gunman prompted police to order everyone inside, and turned the campus into a ghost town. The lockdown was lifted for most of the campus about six hours later.

Police say the ordeal began when they received an anonymous call at around 9:30 this morning from a man who said his roommate was headed to the Yale campus to shoot people.

Initially, police told News 12 Connecticut that more than one person reported seeing a man on campus with a long gun, but they now say there was only one witness, and there is a strong possibility that person may have actually seen a police officer with a gun, and not the suspect

New Haven Police Chief Dean Esserman says that the day’s events started with a "purposeful and malicious call," and adds that he intends to track down and arrest the person who placed the initial call.

Police say their investigation was simplified by the fact that classes are not in session for the Thanksgiving holiday. Some of the students who were still on campus say they were very frightened when they got the alert and they are thankful there was such a strong response by authorities.

For news conference on Yale lockdown, watch the clip to the left or click News 12 Extra on Optimum TV channel 612.