A 3-year-old out shopping for the holidays with his grandmother was shot dead in Little Rock, Arkansas, on Saturday night when an angry motorist opened fire on her car, authorities said.
The male suspect, who has not yet been caught, apparently became enraged because he believed the grandmother "wasn't moving fast enough at a stop sign," spokesman Lt. Steven McClanahan told the Associated Press.
The pair were driving in the city's southwest shortly before 6:20 p.m. local time when the shooting occurred.
McClanahan told CNN the agitated motorist honked his horn at the grandmother, before exiting his car and opening fire on the woman's vehicle, hitting the toddler.
The woman was uninjured and managed to drive to a nearby J C Penny store parking lot where she called police.
The boy was taken to a hospital, where he later died.
"Tonight's homicide was a road rage incident," police wrote on Twitter. "The grandma and 3-year-old victim are innocent and have no relationship...[with] the suspect."
Police said they were searching for "an older black Chevrolet Impala being driven by a tall [black male]."
A police report obtained by the Arkansas Democrat-Gazette newspaper identified the woman as Kim King-Macon, 47, and said she had been driving with the 3-year-old and a 1-year-old when the shooting happened.
According to the report, she said she honked back at the angry motorist, prompting him to leave his vehicle and open fire.
Speaking to local station KATV, the victim's family identified the boy as Acen King.
"I woke up with my little nephew Ace on my mind!" the boy's aunt, Carol King, wrote on Facebook.
In a media briefing late Saturday night, Police Chief Kenton Buckner said this was the second time in a month a toddler had been killed in a road-rage incident, citing the death of a 2-year-old girl shot dead in her aunt's car in November. No suspect has been arrested in that case.
"As you can probably understand, that's very, very frustrating to our police agency, as it should be to our community," he said.
Saturday's death was the city's 40th homicide this year, police said.