The role of violent video games, drugs and potential links to gangs in a neighbouring city are being probed by Oklahoma detectives investigating the murder of Australian baseballer Chris Lane.
Duncan Police Department Detective John Byers says evidence collected from social media posts by the three boys charged in Mr Lane's killing - James Edwards, 15, Chancey Luna, 16, and Michael Jones, 17 - has offered clues, including violent video games they may have played before the murder.
"I've seen some Twitter posts and they talk about Call of Duty," Det Byers said, referring to the popular shooter video game franchise.
Authorities allege Mr Lane, 22 from Melbourne, was jogging alone along Country Club Rd, Duncan, at 2.57pm on August 16 when Luna shot him in the back with a .22 calibre revolver.
Jones drove the car used in the drive-by shooting, while Edwards was a passenger, police believe.
No direct links between the boys and gangs have been found.
However, Det Byers says the investigation continues to examine whether the 107 Hoover Crips and the Piru Bloods, both located in Lawton, 51km away, may have influenced the boys.
"It's something we aren't eliminating and are still looking into," he told AAP on Monday.
Photos of Edwards and Luna on social media show the boys posing with bricks of cash, raising questions how the boys had so much money.
"That's something we are looking into on the narcotics side," the detective said.
"Were they out there slinging dope or committing burglaries and selling stolen property?"
Edwards, Luna and Jones were arrested in a church car park in Duncan four hours after Mr Lane was murdered, with police alleging the trio was at the car park to kill 17-year-old local, Christopher Johnson.
Det Byers said marijuana paraphernalia, along with a shot gun, was in the black Ford Focus the boys were driving.
A fourth juvenile was arrested in the car park, but after being interviewed by police was released.
Edwards, Luna and Jones are being held in protective custody in Stephens County Jail.
Jones, who has talked to police, is separated from the other two boys.
"They are kept in a cell by themselves and the only time they pull them out is for showers and phone calls," Det Byers said.
Edwards and Luna have been charged with first-degree murder and face life in jail without parole.
Jones is charged with being an accessory to murder and has a potential 45-year jail sentence if convicted.
Mr Lane was attending a college in Oklahoma where he had a baseball scholarship.
