Osama El-Atari, seen in an undated photo, was found dead Feb. 13, 2016. Police said they think robbery was a motive. (Loudoun County Sheriff's Office)

Two Maryland men have been arrested and charged with murder in the death of a Loudoun County man who had been a jailhouse informant in a high-profile murder case. But Prince George’s County police said Thursday they do not think the slaying was related to the victim’s past.

Police said Osama El-Atari, 37, a former restaurant owner from Leesburg, was found fatally shot in the upper body Saturday afternoon in his black Dodge Ram 2500 pickup truck on sparsely populated Armstrong Lane in Upper Marlboro, just off Pennsylvania Avenue near Joint Base Andrews.

Investigators think he was killed three days earlier as part of a targeted robbery, Prince George’s Lt. Dave Coleman said.

Court records show that police found a witness Saturday who provided “specific details about how [El-Atari] was killed. These details included a conspiracy amongst several people to rob and assault [El-Atari]” and that two suspects attacked El-Atari in his truck, stole property from him and then shot him. The witness knew that a Rolex watch had been taken from El-Atari, which was not public information, according to a statement of charges by a detective identified as V. Tyler.

Prince George’s police arrested Eric DeAngelo Garris, 29, of Waldorf, and Taqwa Muhammad, 26, of Lusby, on Wednesday afternoon. Both were charged with first- and second-degree murder and ordered held without bond.

Taqwa Muhammad, 26, is one of two men arrested and charged in the killing of Osama El-Atari’. (Courtesy of Prince George's County Police)

Court records show that Garris has an extensive criminal record that dates to a 2003 carjacking case in which he pleaded guilty to assault and was sentenced to four months in jail, and an apparent home invasion in 2012, for which he was sentenced to three years in prison.

Maryland corrections officials said he was denied parole in 2013 and was mandatorily released in October 2014.

He was arrested again last June on a charge of being a felon in possession of a gun and was to be tried next month, court records show.

El-Atari once owned the Original Steakhouse and Sports Theaters in Ashburn and Woodbridge, a fleet of luxury cars and a $3.8 million mansion in Ashburn before his financial empire crashed under a mountain of fraudulent loans he had taken from various banks. He pleaded guilty in 2010 to defrauding the banks of $54 million and was sentenced to 12 years in prison.

But while awaiting sentencing in the Arlington and Alexandria jails, he met other defendants who apparently confessed their crimes to him, including an ex-Marine, Jorge Torrez.

El-Atari tape-recorded Torrez admitting to the slaying of two young girls in Zion, Ill., a crime for which one of the girls’ fathers had been charged.

The tape was played at Torrez’s federal trial in Alexandria for the 2009 murder of Navy Petty Officer Amanda Jean Snell in Arlington, for which the jury sentenced Torrez to death in 2014.

Eric DeAngelo Garris, 29, is one of two men arrested and charged in the killing of Osama El-Atari. (Courtesy of Prince George's County Police)

For his cooperation, El-Atari was released from prison in May 2014 after serving more than four years.

But Prince George’s investigators do not think El-Atari’s slaying was related to the cases in which he was an informant.

“There’s nothing that indicates in any way it was tied to the prior cases,” Coleman said.

He said police were investigating why El-Atari was in Prince George’s and how he might have encountered Garris and Muhammad.

An earlier version of this report incorrectly stated that El-Atari owned the Buffalo Wing Factory restaurants.