WASHINGTON — The internal watchdog at the Environmental Protection Agency has launched yet another investigation of travel and security spending involving embattled administrator Scott Pruitt.

EPA Inspector General Arthur Elkins wrote in a letter that his office will review spending by Pruitt’s full-time security detail at times when he wasn’t traveling for any official purpose. The review was requested by Democratic Sen. Sheldon Whitehouse of Rhode Island, who raised concerns about EPA security spending during a family vacation in which Pruitt went to Disneyland and attended a football game at the Rose Bowl.

Elkins office is now conducting at least a half dozen audits and investigations related to Pruitt and his security team. Separate reviews are also underway by Congressional oversight committees, the Office of Government Ethics and the White House.

READ MORE: AP report: When not flying on taxpayer’s dime, EPA head Scott Pruitt sat in coach