A behind-the-scenes battle is intensifying over who gets a share of the extensive Northern Virginia land holdings of convicted arms dealer Edwin P. Wilson, the former CIA agent who allegedly made millions in illegal deals with Libya between 1976 and 1982.

Wilson, 54, has been found guilty in recent months in federal courts in Alexandria and Houston of exporting arms and explosives to Libya and has been sentenced to 32 years in prison plus $345,000 in fines.

Within hours after his Texas conviction Feb. 5, the former agent signed a document turning over a 707-acre portion of his holdings in Virginia hunt country to his two defense lawyers, Herald Price Fahringer of New York and Marian S. Rosen of Houston.

The land, identified as Bollingbrook Farm on Rte. 712 in Fauquier County, was valued in the document at $350,000 and apparently represented legal fees owed to the two attorneys. Neither Fahringer nor Rosen could be reached for comment yesterday.

Ownership of the property is being contested by federal prosecutors, who filed a lien against the land on Feb. 1, four days before Wilson gave it away. The government's action is intended to ensure that Wilson has the resources to pay the $200,000 fine imposed in the Alexandria case, according to court documents filed by Assistant U.S. Attorney Theodore S. Greenberg.

At the same time, Wilson is involved in lengthy property negotiations in three Northern Virginia jurisdictions with his ex-wife Barbara. The two were divorced on Dec. 5, 1981. Under Virginia law, Barbara Wilson is entitled to a half interest in all property formerly owned by the couple, according to lawyers in the case.

Furthermore, U.S. tax officials on Feb. 17 placed their own lien on all of Wilson's assets in Virginia, alleging that he owes nearly $24 million in unpaid income taxes for 1977 through 1981 -- the years when Wilson allegedly was supplying goods and expertise to train Libyan terorists abroad.

Finally, according to court documents and a source, an insurance company that holds the mortgage on three Wilson properties in Northern Virginia, including Bollingbrook Farm, contends it is owed more than $1 million.

The value of the 707-acre parcel may be considerably higher than $350,000. The most recent Fauquier County tax assessment set a figure of $2.4 million for Bollingbrook. A financial statement carried by Wilson when he was arrested last summer by federal agents also put the land's value at about $3,500 per acre, or roughly $2.5 million.