A 55-year-old Pikesville, Md., woman was indicted in federal court yesterday on charges she strangled an elderly friend whose body was found stuffed into a footlocker that was tossed along a Loudoun County road seven years ago.

Nancy Jean Siegel already was accused of stealing years of Social Security payments that had been intended for her deceased friend, Jasper F. Watkins, 76. Yesterday, a federal grand jury in Baltimore handed up an indictment alleging that Siegel fleeced Watkins while he was alive, killed him when she feared that her scam would be exposed and then continued collecting his Social Security payments. The slaying charge can carry a death sentence.

The case against Siegel may bring to a close a mystery that had perplexed Loudoun sheriff's investigators since Watkins's body was found May 14, 1996, in a black trunk that was dumped near an entrance to the Appalachian Trail. There were few clues to the man's identity, and it wasn't until last January, after consulting a military fingerprint database, that investigators learned it was Watkins, who had served in the Army.

Working together, local and federal investigators learned that Watkins's Social Security checks were ending up in bank accounts used by Siegel, court documents state. About noon Feb. 4, 2003, an agent saw Siegel try to deposit one of the checks, the documents say.

Harold Glaser, Siegel's attorney, said yesterday that his client "murdered no one" but declined further comment. In court documents, he has said that Siegel "constantly cries" and that after her arrest, she attempted suicide.

Federal prosecutors allege that after Watkins died, Siegel stole $89,728 in Social Security payments intended for him and about $10,000 of his retirement annuity. According to the indictment, she used Watkins's name to open credit card accounts and purchased items including jewelry and a car.

Siegel is charged with running a series of scams that began in 1982 and continued until her arrest in August. According to the indictment, she cheated several other people, including her husband and two ex-husbands. In addition to a charge of willfully killing Watkins, Siegel is charged with bank fraud, theft of government property, identity theft, wire fraud and mail fraud.

According to the indictment, Siegel befriended Watkins in 1994. She started using his credit cards and opened other accounts in his name without his knowledge, the indictment states.

While Watkins was alive, the indictment alleges, Siegel lied to medical personnel to have Watkins seem to have dementia and have him committed in a residential facility. When that didn't work, she "attempted to control Watkins by drugging him and depriving him of food," according to the indictment, and by controlling his contact with family and friends.

When investigators asked Siegel about Watkins in August, she told them he walked out of her apartment shouting, "I'm going to get out of here," and then fell down in front of the apartment. Siegel also told investigators that she bathed Watkins and dressed him only in a pajama top. Watkins was found in the footlocker in a pajama top and a pillowcase over his head.

Staff writer Susan Levine and researcher Bobbye Pratt contributed to this report.