Australian authorities are holding two Washington-area fugitives whose arrests here last year on drug charges helped spark investigations by the House ethics committee and the Justice Department into alleged drug use on Capitol Hill.

The two fugitives, Troy M. Todd Jr. of Maryland and Douglas W. Marshall of Washington, were arrested Wednesday in a motel in Kenwick, Australia, a suburb of Perth, by Australian Federal Police. The Australian officials were acting on warrants issued by a federal judge here, according to Drug Enforcement Administration spokesman Robert Feldkamp. He said a DEA agent would be sent to Australia to arrange for their extradition. An extradition hearing is scheduled for Feb. 3.

Marshall, a former congressional page, and Todd were arrested in Washington last April along with a third man, Robert A. Finkel. Finkel alleged to investigators that a ring supplied cocaine and marijuana to government offices and members of Congress. Charges against all three men were subsequently dismissed to give a grand jury more time to investigate the alleged ring.

Marshall and Todd were indicted last November on charges of running a cocaine distribution ring, but had left the country before the indictment, according to law enforcement sources.

The federal and congressional probe into possible drug use on Capitol Hill is continuing.

Law enforcement sources said both suspects were carrying false identifications and had airline tickets to Honolulu when they were arrested. They were traveling with two unidentified Australian women, those sources said.