A 12-year-old girl celebrating her birthday in Chicago was shot in the head while in a car with her family, police said Wednesday.

The girl, whose identity wasn’t immediately available, was listed in critical condition at a hospital, where she’s “fighting for her life” after being critically wounded late Tuesday, Chicago police said.

“Another child has become the victim of senseless gun violence and it must stop,” department officials tweeted. “As she fights for her life, we’ll be relentless in pursuing the offenders responsible for this unfathomable act of violence.”

No suspects had been arrested in the shooting in the city’s Chicago Lawn section as of Wednesday afternoon, a police spokeswoman said.

The girl, who was shot in the back of her head, was rushed to a hospital by relatives at about 7:45 p.m. on Tuesday. She was later transferred to Comer Children’s Hospital, where she’s listed in critical condition, police said.

The girl has severe brain injuries, according to a police report obtained by the Chicago Tribune. She had been sitting in the passenger seat of a car driven by a relative when she was wounded as three men started firing at another car from the street. Her mother was also inside the vehicle, the report states.

The gunmen were targeting another car that sped past the family’s vehicle, police said in the report, which noted video footage of the incident has been obtained by investigators. That footage has not been released to the public, the Tribune reported.

The girl’s family, meanwhile, is shattered by the shooting, Chicago activist Andrew Holmes told WGN-TV.

“We need to seriously start turning these individuals in,” Holmes said. “If you have any video surveillance, any knowledge, license plates, anything – it doesn’t matter. This child is fighting for her life.”

Shootings and homicides in Chicago are down 5 percent and 1 percent, respectively, this year compared to the same span a year ago, Chicago Police Superintendent David Brown told reporters Wednesday at a press briefing alongside Mayor Lori Lightfoot.

Brown angrily vowed cops would arrest those responsible for shooting the 12-year-old girl as she left her birthday dinner.

“The Chicago Police Department will bring the full force of this department to solve this crime,” Brown said. “This was heinous, reckless, senseless, and the gangs involved – you know who you are – we’re coming after you. We’re coming after you.”

Seven other people were wounded Tuesday by gunfire elsewhere in the Windy City, the Chicago Sun-Times reported. A day earlier, seven people were shot, including three fatally, according to the newspaper.

Anyone with information should call Chicago police at (833) 408-0069 or (312) 746-7330. Tips can also be submitted anonymously at CPDTIP.com. A $15,000 reward is being offered for information leading to a break in the case, Brown said.