He was hundreds of miles away and behind bars, but that didn't stop former CIA operative Edwin P. Wilson from throwing a monkey wrench today into plans to auction off his prime Fauquier County farmland, appraised at $7.4 million.

As knots of well-dressed men and women gathered at 2 p.m. on the steps of the county courthouse to bid on 2,748 acres of property near Upperville belonging to Wilson and his former wife, they were told that the ex-spy had filed for bankruptcy late Monday in Trenton, N.J.

That froze all action on the land, which is in the middle of Virginia's fashionable horse country here, and left the auction crowd grumbling.

"It's an annoyance," said Bolling Powell Jr., attorney for Barbara H. Wilson, Wilson's ex-wife, "especially with all the money and promotion to publicize this thing."

Even Robert T. Mitchell Jr., one of Wilson's own attorneys, said he was caught by surprise when he arrived in Warrenton this morning. He said he did not know why Wilson chose New Jersey as the place to file for bankruptcy.

County officials said they could not remember another auction involving as much prime property as the Wilson farms. "The farms are right in the heart of some of the most beautiful property in America," said Dennis Ownby, the auctioneer whose task today was simply to announce that the auction had been stayed.

Wilson, 56, is serving a 52-year term at the maximum security federal prison in Marion, Ill., on three separate convictions, including attempted murder, gun-running and smuggling 20 tons of high explosives to Libya in the late '70s. He was fired from the CIA in 1971.

The auction was set after his former wife filed suit to divide property they owned jointly. The two were divorced in 1981.

Powell, Barbara Wilson's attorney, said New Jersey federal bankruptcy court Judge Amel Stark probably would transfer the matter to federal court in Alexandria and that his client would then file a petition to rescind the stay on the auction.

"There's every reason to think the court will grant the petition because bankruptcy court would rather have cash than real estate," Powell said.

Powell said the proceedings probably would be delayed only about a month, and the auction would be rescheduled unless offers for the property have been accepted privately in the meantime. A county Circuit Court judge must approve any bids accepted for the properties.

A $2 million contract for one of the largest of the Wilson properties, the 707-acre Bollingbrook Farm, was filed in Fauquier Circuit Court before the scheduled start of the auction today. The prospective buyer, Rose Marie Bogley of the Peace & Plenty Farm in Middleburg, made a deposit of $200,000 on the property, according to court papers.

Mitchell said a number of offers have been made for the other properties.

Barbara Wilson does not live on any of the properties that were scheduled for auction today, Powell said.

If the sale goes forward, it is unlikely that Edwin Wilson will see his portion of the proceeds. The Internal Revenue Service has a lien of $24 million on all his property.