A Fairfax County man has been charged with first-degree murder in the death of his ex-wife, whose body was found last week floating near a Potomac River boat landing in Loudoun County, officials said yesterday.

Jaime Traverso, 36, of 531 Florida Ave. in the Herndon area, is being held under $50,000 bond at the Loudoun Adult Detention Center in Leesburg, according to Sgt. Terry McCracken of the Loudoun County Sheriff's Department.

Two fishermen discovered a woman's body floating in the Potomac at McKinney's Boat Landing 12 miles north of Leesburg about 9:30 a.m. on July 30, McCracken said.

Investigators believed she had drowned until an autopsy report showed that she had been strangled and had several knife wounds on her chest, according to McCracken. He said the autopsy also indicated that she had been dead less than 24 hours.

The body remained unidentified for two days, until Loudoun officials received notice from Fairfax County authorities that Jaime Traverso had filed a complaint that his former wife, Antonia Traverso, 32, had abandoned their three children.

Loudoun authorities were able to identify the body as that of Antonia Traverso last Friday after showing family members pictures of the body, McCracken said.

Jaime Traverso, who was divorced from his wife late last year, was arrested later that day, McCracken said.

Investigators said they believe from interviews with the three Traverso children that Jaime and Antonia Traverso had been together on the night of July 29, according to an affidavit for search warrant filed by Fairfax County police.

The affidavit also says that Jaime Traverso was seen by a Loudoun County sheriff's deputy at about 2:30 a.m. on July 30 driving a vehicle on Rte. 15, just south of the spot where his ex-wife's body was found later that day.

The Traversos came to this county from Panama, McCracken said, although he said he had no details on how long they had been married or how long they had lived in Northern Virginia.