The group of children probably thought they were in for a night of harmless fun. The activity? Chucking snowballs at passing cars in a residential area on Milwaukee’s northwest side.

But then, police say, things took a dangerous turn when one driver retaliated against the kids — with a gun.

Shortly before 8 p.m. Saturday, officers from the Milwaukee Police Department responding to a report of a shooting arrived to find a 12-year-old girl and a 13-year-old boy suffering from gunshot wounds. It didn’t take long for authorities to figure out what had triggered the act of violence: a single snowball.

“Preliminary investigation indicates both victims were with a group of juveniles throwing snowballs at cars passing by,” the police department wrote in tweets Monday. “One of the snowballs struck a white Toyota, no further description, and the driver of the auto fired shots into the group of kids striking the two victims.”

Officers at the scene provided first aid to the children, who sustained non-life-threatening injuries and are now recovering at a Milwaukee hospital. A search is underway for the driver, and as of Monday night, no arrests had been made, ABC News reported. Investigators, who are asking for any information related to the case, are looking for home-surveillance video that may have captured the shooting, WISN reported.

In a city where gun violence was the leading cause of homicides last year, the circumstances of Saturday’s shooting left residents and local leaders unsettled.

“Over a snowball you’re going to kill somebody?” Pearlee Piggue, who heard the shots while cooking dinner, told WDJT. “It’s ridiculous.”

Alderman Cavalier Johnson, whose district includes the scene of the shooting, was equally appalled by the driver’s alleged action.

“They could have let down the window and told the kids not to do that,” Johnson said. “They could’ve yelled at the kids. They could’ve chased the kids home, told their parents.”

Though several people were shocked that a snowball could prompt such violence, there have been a handful of similar cases nationwide.

A Philadelphia teen was fatally shot in the head in 2008 after he threw a snowball that hit a passing adult in the face. In 2009, a D.C. police detective pulled out his gun during a confrontation with a group of people who pelted his squad car with snowballs. More recently, a woman in Seattle was arrested last February for allegedly trying to run over people having a snowball fight when one of the icy projectiles smacked her Jeep.

Milwaukee police didn’t specify how many shots were fired from the white Toyota on Saturday night, but one person told WISN she counted up to five.

The gunfire sent Ravell Davis and his family scrambling for cover inside their home nearby, fearing they could be struck by an errant bullet.

“Me and my wife, we got six kids, we in the kitchen [and] all of the sudden you hear all these loud booms, so I actually told everybody to get down,” Davis told WISN.

Davis later added: “It’s getting bad. You know, it’s ridiculous when you look outside and the front and the side of your house is taped off. It’s getting real crazy now.”

Since 2014, Milwaukee has seen higher rates of homicides and nonfatal shootings, according to the Justice Department’s Project Safe Neighborhoods initiative. Data gathered by the Milwaukee Journal Sentinel found there were nearly 100 homicides in the city last year and more than 80 percent of the cases were shootings.

Saturday’s incident should serve as yet another example of the necessity of gun legislation, Johnson told WDJT.

“Gun laws in this state are decided in Madison,” he said, referencing the state capital. “Once again, I’m asking for the people who control the legislature, to do something about this so we don’t have situations like this in this city or anywhere in Wisconsin.”