Updated: 3:36 p.m.

A Congressional watchdog organization called Monday for an investigation into whether Rep. Bob Etheridge’s (D-N.C.) altercation with an unidentified youth earlier this month violated House rules.

In a letter to the Office of Congressional Ethics, the conservative group Judicial Watch requested a probe into Etheridge’s rough handling of a self-identified student, captured in a video that garnered national attention last week.

“It is essential that the House holds Congressman Bob Etheridge to the high standards of behavior expected of a Member of the House,” Judicial Watch President Tom Fitton wrote in the letter. “Congressman Etheridge acted out in a violent and threatening manner in response to an unremarkable inquiry by a member of the public. The public confidence in Congress has diminished as a result.”

In the video posted on multiple websites last week, a man identifying himself as a student asks Etheridge whether he “fully supports” President Barack Obama’s agenda. Etheridge grabs the student’s arm and demands to know who he is, and then pulls the man next to him.

“We are aware of media reports of a complaint filed by a Washington, D.C. conservative political activist group with the Office of Congressional Ethics (OCE),” Etheridge spokesman Don Owens said in a statement to Roll Call. “Our office has not been contacted by the OCE. Congressman Etheridge has apologized to all involved and would personally apologize to the two individuals if he knew who they were. He continues to work on the priorities of the people of North Carolina’s Second District, focusing on creating good jobs, building new schools, making health care more affordable, protecting Medicare and Social Security and standing up for our veterans and those who keep America strong.”

Etheridge earlier issued an apology June 14 for the incident.

The OCE reviews potential rules violations and refers investigations to the House Committee on Standards of Official Conduct, also known as the ethics committee. Only the House ethics committee may sanction Members, however.