At the time of his death, Jonathan P. Luna had about $25,000 in credit card debt, the official said.
Other sources said Luna, 38, had expressed concern in recent weeks that he had fallen out of favor with his supervisors at work and might have to change jobs - a notion Maryland U.S. Attorney Thomas M. DiBiagio flatly denied last night.
The law enforcement official, who spoke on the condition of anonymity, said federal agents also were reviewing adult pornographic files found on Luna's Justice Department computer that appeared unrelated to his caseload, which had included the prosecution of online child pornography and predators.
As authorities were compiling extensive information about Luna's personal life and his final hours, they continued searching for a suspect in his killing.
Top officials who met yesterday to discuss the case said in a statement that the FBI, U.S. Marshals Service and Pennsylvania State Police would continue to jointly investigate and that no jurisdictional decisions are possible "until all the facts and circumstances are known."
Law enforcement sources had indicated over the weekend that the investigation likely would be handled as a local murder case in Lancaster County, Pa., where Luna's body was found shortly before dawn Thursday.
He had been stabbed 36 times, beaten and left face down in a shallow creek. Among Luna's wounds were injuries to his genital area, law enforcement sources have said.
Investigators believe that Luna's death was the result of a personal relationship that turned violent, not a random crime or in retaliation for his work - reducing the likelihood that his death would be prosecuted as a federal crime.
But the case remains a sensitive and painful one for federal prosecutors in Baltimore.
At the downtown courthouse yesterday, many employees from the office wore black ribbons on their lapels; flags outside the building flew at half-staff.
"The investigating agencies and prosecutors' offices continue to work jointly to find the person or persons responsible for this crime," DiBiagio and Lancaster County District Attorney Donald R. Totaro said in a statement.
Both prosecutors have declined to comment further on the investigation. But last night DiBiagio rejected any suggestion that Luna had been at risk of being fired.
"His job was not in jeopardy in any respect," DiBiagio said.
He said Luna's prosecution earlier this year of a rare pornography-production case was recognized by the office as "one of the most significant prosecutions of 2003."
DiBiagio also said Luna had expressed no concerns about his job security at an employee review meeting in June and had no reason to: None of Luna's supervisors "ever indicated we should take any ... action against him."
Luna, a married father of two who joined the federal prosecutor's office four years ago, was stylish and energetic and showed promise as a young lawyer.
The Bronx, N.Y., native and graduate of the University of North Carolina law school had previously worked as an assistant district attorney in Brooklyn, N.Y., and served as a staff attorney at the Federal Trade Commission. He was an associate at the Washington law firm of Arnold and Porter in 1993 and 1994.
Luna's parents, Paul D. and Rosezella Luna, have said they believe his death was related to his work prosecuting violent criminals and have steadfastly rejected suggestions that he had affairs or money problems.
As an assistant U.S. attorney, Luna handled a range of cases, but among his more notable was the prosecution this year of a Navy physicist who was accused of trying to seduce a teen-age girl on the Internet, but who claimed he was only engaged in online fantasy.
Late last year, Luna won convictions in a string of violent Baltimore County bank robberies in a curious trial that produced its own mystery: At the end of the trial, authorities discovered that more than $36,000 in cash disappeared somewhere between the courtroom and the government storage area used to hold sensitive evidence during trials. That loss was never solved.
In recent months, lawyers who had worked with Luna said that he appeared to be distracted and disorganized. Three legal sources, who spoke on the condition of anonymity, said Luna had indicated that he was exploring career options outside of the prosecutor's office.
When he disappeared last week, Luna was concluding a drug conspiracy trial in U.S. District Court against two Baltimore men who were accused of running a violent heroin ring from the recording studio of their upstart rap music label, Stash House Records.
Late Wednesday, Luna had told a defense attorney in the case that he was returning from home to the federal courthouse to complete paperwork for expected plea deals in the case the next morning. He left the courthouse about 11:30 p.m., according to building records, and his body was found about six hours later in rural Brecknock Township, Pa.
Investigators have built a detailed timeline of Luna's travels during those hours, according to law enforcement sources. Luna is believed to have set out on the trip willingly and headed toward Philadelphia - not Lancaster County - using an EZ Pass card to slip through toll booths in Delaware and Pennsylvania and making at least two stops: one to withdraw money at an ATM and another where he used a credit card to buy gasoline in King of Prussia, Pa., a busy retail center west of Philadelphia.
Authorities were looking for signs of any other activity on Luna's credit or bank cards.
Over the weekend, federal agents asked Luna's family about other trips he might have taken in recent months to the area where his body was found.
They also were examining messages posted by someone using the name Jonathan Luna on Internet dating sites. The author of the messages, from April 1997, described himself as a discreet, 31-year-old married black man seeking a white female sexual partner and indicated a preference for blondes and redheads.
A law enforcement official said yesterday that investigators were closely examining relationships that Luna had with at least two women. The official did not elaborate on the nature of the relationships.
In Lancaster County, FBI agents have questioned hotel operators near the crime scene about any unusual activity the night of Luna's disappearance.
The agents have asked specficially about unusual activity in hotel parking lots and asked to review guest registers and any outdoor surveillance cameras.
Agents made similar stops at gas stations near the crime scene and along the route that authorities think Luna traveled, according to business operators and law enforcement sources.
Sun staff writers Gus G. Sentementes and Lynn Anderson contributed to this article.