A 1-year-old is in grave condition after he was shot in the head during an apparent road rage incident in Chicago, officials said.

The shooting occurred around 11 a.m. local time Tuesday on Lake Shore Drive, police said.

Shots were fired for approximately two blocks along the expressway, during which a nearly 2-year-old child was struck in the head, Cmdr. Jake Alderden of the Chicago Police Department’s 1st District told reporters during a press briefing a few hours after the incident. Multiple shell casing were recovered across those two blocks, he said.

The drivers appear to be “completely unknown to each other,” Alderden said.

“There was a dispute possibly over somebody not letting somebody into a lane of traffic,” he said.

The vehicle carrying the child continued driving before crashing shortly after on Lake Shore Drive.

A good Samaritan took the toddler and other occupants of the car to Northwestern Memorial Hospital, police said. From there, he was transferred to Lurie Children’s Hospital, where he was in critical condition, Alderden said.

Police recovered a handgun from the crashed car and are determining if it was fired during the incident, the commander said.

The police district plans to release a description of the car involved in the incident, Alderden said.

Mayor Lori Lightfoot said that detectives have a suspect and are “actively pursuing the other car.”

“Obviously any time anyone is shot in Chicago it is tragic, particularly when it is a child,” the mayor said during a press briefing Tuesday afternoon. “This was simple, but stupid, road rage.”

The victim was receiving full critical care support, including the use of a ventilator, in the pediatric intensive care unit, Lurie Children’s Hospital officials said Tuesday afternoon.

“He is in grave condition,” Associate Chief Medical Officer Dr. Marcelo Malakooti told reporters during a press briefing outside the hospital. “It’s a very serious bullet injury.”

The child was believed to have suffered one bullet wound and sustained a brain injury, Malakooti said.

“It’s a very tenuous situation,” he said. “It can change hourly for us.”

Ja’Mal Green, a Chicago community activist, is offering a $5,000 reward for information leading to the arrest of the gunman.

“This should not be our reality,” Green, who is the father of a 2-year-old, said at a media event Tuesday. “We have to bring this horrible person to justice.”