An Atlanta homicide suspect's identical twin is surprised by accusations that his brother killed a man.

"I know he isn't the type of person to do that," Jessie Stewart told the Atlanta Journal-Constitution on Thursday.

Stewart's brother, 34-year-old James B. Stewart, was arrested Monday on accusations that he shot and killed Doug Perry of suburban Denver on July 3 at a BP station at 3260 Donald Lee Hollowell Parkway.

Perry's friend, Jay Holden, said Perry was a horse owner and was likely returning from a farm he owned in Alabama via Hartsfield-Jackson Atlanta International Airport.

Holden said Perry had stopped at the BP to refuel his rental car before returning it and boarding his flight home,

and suggested that the confrontation with James Stewart may have been the result of a robbery that Perry resisted.

"If somebody was just trying to take money from him, I can't imagine he would've just given it over willingly," Holden told Denver's KCNC-TV News.

But Jessie Stewart, while acknowledging his brother had a criminal past, said James Stewart wouldn't pull off a robbery, much less a murder.

"I've never known him to rob anybody," Jessie Stewart said. "He's been in jail for theft by receiving or breaking into cars."

Witnesses who live in the neighborhood where the shooting happened, and who know James Stewart, gave police a different story, according to an arrest warrant obtained by The Atlanta Journal-Constitution.

"A witness on the scene observed the male who he only knew as 'Fat Man' walk across the street to the BP after parking at a nearby Texaco, and approach Mr. Perry at the pump," police records said.

Police say the man identified as "Fat Man" shot Perry three times before fleeing to his car parked across the street.

Investigators contacted Jessie Stewart in hopes of finding James Stewart.

"They talked to him on my phone," Jessie Stewart said. "I don't know what he told them."

Jessie Stewart did acknowledge that his brother claimed to be defending himself.

"He said it was self-defense," Jessie Stewart said.

According to police, James Stewart told investigators that Perry was holding something in his hand and "came after him."

In addition to murder charges, James Stewart was charged with possessing a gun during the commission of a felony and gun possession by a convicted felon, stemming from a 2006 conviction on a drug arrest, according to court records.

He is being held without bond at the Fulton County jail and is scheduled to be back in court on July 31.