The video -- posted by Crossingbroad.com and more widely circulated via Deadspin -- depicted an agitated Cooper, who is white, telling a companion, "I will fight every (expletive) here."
On Wednesday, Cooper released a statement through the team apologizing for his behavior.
"I am so ashamed and disgusted with myself. I want to apologize," the statement read. "I have been offensive. I have apologized to my coach, to Jeffrey Lurie, to Howie Roseman and to my teammates. I owe an apology to the fans and to this community. I am so ashamed, but there are no excuses. What I did was wrong and I will accept the consequences."
Eagles owner Jeffrey Lurie released a statement on the matter shortly thereafter.
"We are shocked and appalled by Riley Cooper's words," Lurie said. "This sort of behavior or attitude from anyone has no role in a civil society. He has accepted responsibility for his words and his actions. He has been fined for this incident."
Cooper then met with reporters, answering questions for nearly six minutes. He apologized repeatedly, explaining that he was raised better and that he handled the situation "extremely poorly." He said he had yet to meet with teammates and added that he'd been fined "a good amount of money."
He acknowledged that he had been drinking during the concert and his confrontation was with an African-American security guard. The video had been brought to his attention just hours before it circulated on the Internet.
"This is the lowest of the lows," he said. "This isn't the type of person I want to be portrayed as, this isn't the type of person that I am. I'm just extremely sorry."
This obviously is a bad look for Cooper, who had some unpleasant explaining to do in the Eagles' locker room. The video surfaced during a time when Cooper has taken on a larger role with the team following Jeremy Maclin's season-ending knee injury Saturday.
For now, that takes a backseat.
UPDATE: NFL Commissioner Roger Goodell told ESPN Radio's "Mike and Mike" on Thursday that the NFL won't punish Cooper at the league level. He called Cooper's comments "obviously wrong and they're insensitive and they're unacceptable."