Loudoun County Supervisors Chairman Scott K. York (R-At Large), employing the tough rhetoric that has brought him strident support and fierce opposition, formally launched his reelection bid with a sharp-tongued attack on the Republicans vying to challenge him in November.

A month after bolting the local Republican Party, contending that it had been co-opted by special interests, York blasted his opponents and their backers as "enemies of progress" who were "massing their troops" for a campaign of deception.

"They know they can't win if they tell the truth to the voters, so they will pretend that they don't want to undo anything that we have achieved under my leadership," said York, who is running as an independent. "I know that the residents will not be fooled by their empty rhetoric and bending of the truth to accomplish their scheme."

Supporters who gathered at the Leesburg Holiday Inn on Monday included Democratic Supervisor Eleanore C. Towe (Blue Ridge), independent Supervisor William D. Bogard (Sugarland Run) and several Republicans, including Frank Naylor, undersecretary of agriculture during the Reagan administration.

"Scott has been a good Republican," Naylor said. "We want to see him get reelected."

York did not refer by name to the three candidates seeking his job -- Republican land-use lawyer Robert M. Gordon, former GOP supervisor Larry Beerman and Democrat Alfred P. Van Huyck, former head of the county Planning Commission who helped to engineer strict new land-use regulations passed by supervisors in January in an attempt to reduce home building sharply.

But York's remarks seemed designed to cast Gordon and Beerman as part of what he called a concerted and dishonest effort by development interests and other outspoken opponents to repeal those regulations.

"That's pretty diabolical, isn't it?" Beerman said. "It's obviously campaign season. . . . When he talks about lies and truths, I think at the end of the day one needs to look at Scott's poor fiscal record."

York, Beerman and Gordon have sought to make fiscal stewardship a campaign issue. York says the new building restrictions will mean less spending on schools and other infrastructure. York's opponents say the chairman has led the board in a spending spree that has resulted in higher tax bills.Beerman maintains that downzoning in western Loudoun -- which allows one house per 10, 20 or 50 acres, depending on location, and is the centerpiece of the new slow-growth rules -- went too far and must be reconsidered.

Gordon has said he would not call for reversing the downzoning but would reconsider other aspects of the regulations. He declined to comment on York's remarks, saying he would rather concentrate on winning support of delegates who will choose nominees for various local offices at next month's Republican Party convention.

Gordon and Beerman recruited many of the approximately 2,000 delegates signed up for the convention. They are appealing to others for support.

The candidates were aided in their recruitment effort by supporters who sent barrages of e-mail appeals, including one from Stephen T. Schulte, vice president of Brambleton Group LLC, which is building a 6,000-unit subdivision near Dulles International Airport. Schulte's e-mail March 17 called on recipients to sign up delegates to support Gordon.

"The current political regime is so far out of bounds that I feel compelled to assist in every way possible," Schulte wrote. "Whether you are a democrat or a republican . . . we need your participation . . . to ensure that Bob Gordon Receives the republican nomination."

Schulte said the county was spending millions of tax dollars on lawyers fees to defend building restrictions that are "out of touch with reality." Brambleton filed one of the nearly 200 legal challenges.

Schulte said the e-mail was intended for colleagues in the building community and was sent mistakenly to county government officials and others. He said it did not necessarily represent the views of his company.Gordon said he was "proud to have Stephen Schulte's support" but added, "I haven't been encouraging any Democrats to sign up for the Republican convention."

SCOTT K.YORK