Tuesday evening’s session of the D.C. National College Fair at the Convention Center could have been a game-changing event in the lives of some of the estimated 2,000 students and their families who were expected to attend. Under one roof, more than 300 representatives of colleges and universities from the U.S., Canada and Great Britain were going to be available for one-on-one meetings. Students could visit a counseling center to discuss their choice of majors and get information about financial aid.

But Events DC, which operates the convention center, pulled the plug on the 6 p.m. session after a fight broke out among a small group of the estimated 7,000 students who came to the morning session. The morning event, scheduled to end at 1 p.m., was suspended at about 11:45 a.m. and the students were evacuated with assistance from the police.

There were no injuries or arrests, according to the D.C. police. A Twitter reference to a stabbing that circulated Tuesday was false. But in a statement Tuesday, Events DC said “disruptive activity” posed unspecified safety considerations for the evening segment, scheduled to begin at 6 p.m. — six hours later.

“Public safety remains our utmost concern and priority for our attendees,” Events DC told The Post’s Martin Weil on Tuesday evening.

But Marc Caposino, communications director for OSSE, which co-sponsored the event with the National Association for College Admission Counseling, said he was told by other District officials that it was not security concerns but a complaint about noise that led to the scuttling of the evening program.

Caposino said he was told the complaint came from another group using the center that day. The calendar on the convention center site shows only one other event scheduled for Tuesday: LeadingAge (formerly known as the American Association of Homes and Services for the Aging), an association of non-profits, was in the third day of a four-day annual meeting. According to the official conference schedule the Tuesday session ended at 5 pm, an hour before the College Fair evening session was set to begin.

So, what noise?

Convention center senior vice president and general manager Samuel Thomas did not respond to e-mail or phone messages left Wednesday morning. LeadingAge spokeswoman Lauren Shaham said she wasn’t aware of any noise-related issue raised by her organization. She said she would look into it but never called back.

Caposino said he’s not aware of plans any plans to reschedule the college expo. He finds the whole episode regrettable.

“To be honest, the sad thing was the reaction by the convention center was such an overreaction,” he said. “It was an enormous disservice to the kids and parents who were planning to go that night.”