04/21/2012 02:39 pm ET Updated Dec 06, 2017

Chuck Grassley Secret Service Letter: White House Staff Focus Of Senator's Inquiry (DOCUMENT)

As the Secret Service prostitution scandal deepens, a top Republican on the Senate Judiciary Committee has engineered an inquiry into whether more individuals were involved.

Sen. Chuck Grassley (R-Iowa) sent a letter to Secret Service Director Mark J. Sullivan and Acting Inspector General Charles Edwards Friday evening questioning whether White House Staff members were part of the prostitution scandal. The groups in Grassley's query were the White House Communications Agency and White House Office of Advance, "given the close working relationship among members of advance teams," a press release said.

"More work remains to investigate and uncover what occurred, hold those responsible accountable, and to put in place new policies and procedures to prevent future misconduct," Grassley wrote.

White House Press Secretary Jay Carney said on Friday that he was unaware of any White House staff being involved in the incident.

"I do not know otherwise that this did not involve anything but the agents and the military personnel," Carney told reporters.

Six Secret Service employees have lost their jobs in the wake of allegations that agents had prostitutes in their hotel rooms during an April summit in Colombia. Reuters reported on Saturday that a 12th employee connected to the case lost his or her security clearance and was sent on leave.

Read Grassley's full letter below (via the senator's website):

Chuck Grassley Secret Service Letter