A person wielding a baseball bat attacked two staff members in Democratic US Representative Gerry Connolly's district office in northern Virginia on Monday, Connolly and local police said.
The suspect, who arrived at Connolly's office asking for the congressman, is now in custody, Fairfax City Police said in a statement.
"The thought that someone would take advantage of my staff's accessibility to commit an act of violence is unconscionable and devastating," Connolly said in a statement.
Both staffers were transferred to a hospital with non-life threatening injuries, he said.
Connolly, 73, has served in the House since 2009, representing a district that covers Virginia suburbs to the west of Washington, DC.