Two ex-lobbyists for the Unisys Corp. agreed to plead guilty in the defense corruption scandal Friday to election-code violations stemming from an alleged scheme to funnel illegal, unreported campaign contributions to members of Congress, sources familiar with the inquiry said Thursday.

One source, confirming an ABC News report, said the money was intended to aid, among others, Rep. Roy Dyson, D-Md., and former Rep. Bill Chappell, D-Fla., who was narrowly defeated in his re-election bid last fall following revelations of his ties to defense contractors. There was no indication that the lawmakers were aware of receiving any illegal donations, sources said, and it was unclear whether they would be identified in court papers filed Friday.The sources said former Unisys lobbyists Joseph Hill and Robert Barrett, who have agreed to plead, allegedly were involved in a scheme to file false invoices with Unisys to generate cash for campaign contributions. Barrett only agreed to plead guilty on Thursday, they said.

According to sources familiar with the inquiry, the case marks only the first public disclosure of what are expected to eventually lead to revelations that millions of dollars in unreported defense industry campaign contributions were laundered to members of Congress.