What started out as a cause for celebration turned violent on the streets of Baltimore on Sunday.

After watching his Ravens defeat the nearby rival Washington Commanders, one fan dressed in a Lamar Jackson jersey cranked things up several notches post-game.

In a video that has spread on social media, a white male is seen brutally attacking two Washington fans and appearing to knock one of them unconscious.

In the video, the Baltimore fan approaches two fans in Commanders jerseys and launches an attack on both of them up as the man recording the repeatedly yells, “We’ve got a straggler!”

WARNING: Strong language and violence

After kicking and punching the two visiting fans, the Ravens fan yelled, “I don’t lose! I don’t f—ing lose!”

A Baltimore Police spokesperson told the New York Post that the department is “actively investigating” the incident.

“The Baltimore Police Department is aware of a social media video depicting an assault occurring near Cross St. in our Southern District,” a spokesperson said in a statement.

“Currently, there have been no reports or calls made to police concerning this incident. Detectives are actively investigating the video. Anyone possessing information related to this incident is encouraged to contact the Southern District at 410-396-2499 or Metro Crime Stoppers at 1-866-7-Lockup.”

While the local police were hard at work tracking down the fan involved in the incident, several social media sleuths also got down to business and apparently found an alleged culprit.

In replies to the video posted by Hater Report, which has been viewed more than 45 million times as of Tuesday afternoon, an X user posted information about the man alleged to be the assailant.

While police did not name the suspect, users identified him as Jack Callis, an employee at insurance firm Maury Donnely and Parr. 

However, after the video went viral, the firm announced on X on Tuesday that Callis was “no longer employed” by company. 

“MDP has a zero-tolerance policy for violence and aggressive behavior. This individual is no longer employed with our firm,” the company wrote in its post. 

In Sunday’s game, the Ravens defeated the Commanders 30-23 to move to 4-2 on the season.