DALLAS — An 18-year-old will be charged with murder in connection to an Oak Cliff shooting, authorities say. 

On Aug. 20, police found the victim, 67-year-old Oluwafemi Joseph Ogundana, gunned down inside his car near the 1500 block of Harbor Road.

Ogundana was taken to the hospital where he died, police said.

Detectives say Terrius Randolph, 18, is responsible for the shooting death. 

Authorities say Ogundana met up with Randolph on the day of the shooting to sell him a cellphone. 

RELATED: Man, 67, gunned down inside his car in east Oak Cliff

An arrest warrant says the two men had been communicating about the sale on an app called "Letgo." Randolph allegedly used a fake name on the app, but the profile linked back to his home address, officials say. 

At about 2:30 p.m. on the day of the shooting, witnesses saw Randolph go up to Ogundana's car, knock on the passenger window and get into the vehicle, according to an arrest warrant. 

At one point, witnesses heard the men arguing and then Ogundana was heard saying, "Don't shoot me," according to the arrest warrant. 

Shortly after, witnesses heard a gunshot. Authorities say Ogundana drove a few feet before the suspect shot him several more times, the arrest warrant says. 

Randolph was then seen getting out of the car and running into a house in the area. Investigators say Randolph lived at this residence with his mother. 

SWAT arrived at the residence but cleared the scene after they couldn't locate the teen, the warrant states.

Officials interviewed Randolph's mother who told police her son is part of a gang called "Jugg Team." When police asked her what the gang does, she responded, “You know robberies, they jack people," the arrest warrant states.

Police say earlier that morning, Randolph posted a photo on Instagram wearing a white T-shirt and pink shorts, with a gun under his leg while sitting in a car. This is the same outfit witnesses described Randolph wearing during the shooting, the arrest warrant states. 

A few days after the shooting, detectives say a witness identified Randolph in a photo lineup. 

Authorities plan to charge Randolph with capital murder. He is already in jail for unrelated charges, police say. 

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