U.S. Rep. Sean Duffy (R-Wis.) speaks during the Republican National Convention at the Tampa Bay Times Forum on Aug. 28, 2012, in Tampa, Fla. (Mark Wilson/Getty Images)

Authorities are investigating a report that U.S. Rep. Sean Duffy (R-Wis.) was assaulted Wednesday night by a bystander in the Longworth House Office Building while en route to the Capitol for a vote, according to his office and police.

Few details were immediately released. Officer Shennell S. Antrobus, a spokesman for the U.S. Capitol Police, confirmed that an assault investigation is underway. He said no arrests have been made.

Duffy’s spokeswoman, Cassie Smedile, issued a statement describing the encounter as a “minor incident.” The statement said that “a random individual, unknown to the Congressman, began screaming at him and grabbed his arm.”

Smedile said in the statement that Duffy was not hurt and that he reported the incident to authorities. “Congressman Duffy has requested no further action be taken,” the statement said.

The incident was first reported by Roll Call.

The spokeswoman declined to comment further. She would not say what the man was screaming and whether it was over the government shutdown. Duffy has voted with the block calling for a delay in implementing the president’s health care plan.

Duffy is a former district attorney from Wisconsin who also appeared on the MTV reality show “The Real World,” where he met his wife.