Suspect in Road Rage Killing of 3-Year-Old Boy Charged With Capital Murder

— -- Police have arrested and charged a suspect in connection with last Saturday's road rage killing of three-year-old Acen King in Little Rock, Arkansas, officials confirmed to ABC News.

The suspect, 33-year-old Gary Holmes, was arrested for the shooting and is being held at the Pulaski County Detention Center in Little Rock.

Holmes was booked late Thursday night on charges of terroristic acts and capital murder, records show.

Little Rock mayor Mark Stodola said the suspect was turned in by his relatives to authorities Thursday evening and was interviewed by Little Rock Police detectives.

Terrance Long, the pastor of the boy's family, tells ABC News that the family was told by police that a suspect was taken into custody.

The toddler was out on a shopping trip with his grandmother, Kim King-Macon, when he was gunned down. His infant sibling was also in the vehicle at the time, but he was unharmed, as was King-Macon.

Little Rock Police had said King-Macon told officials that a man in an older black Chevrolet Impala opened fire on her car at a stop sign after becoming agitated that she was not driving fast enough.

King-Macon said she did not realize her grandson had been hit until she pulled into a nearby shopping mall's parking lot, where she called police.

Acen was transported to Arkansas Children's Hospital where he died.

Little Rock Police tweeted on Saturday, "Tonight's homicide was a road rage incident, the grandma and three-year-old victim are innocent and have no relationship [with] the suspect."

Local and federal authorities had offered a combined $40,000 reward for information leading to the arrest and conviction of the suspect.

This story is developing. Please check back for updates.

ABC News' Dominick Proto and Brendan Rand contributed to this report.