Panicked children and adults ran for their lives Monday as at least six people were killed and dozens more were wounded in a mass shooting that took place during a Fourth of July parade in the Chicago suburb of Highland Park.

Veteran Chicago Sun-Times reporter Lynn Sweet, who described the scene of the shooting as a “bloodbath,” said she saw blankets covering three bloodied bodies and five other people wounded and bloodied near the parade viewing stand.

More than 30 people who were wounded, mostly by gunshots but some from the ensuing chaos at the parade, were taken to local hospitals.

“We have an active shooter situation in Highland Park, at their parade. It’s been reported that there’ve been nine people shot,” Illinois Gov. J.B. Pritzker said. “I’ve been in touch with our state police, who are backing up local police and hoping to keep the crowd safe there.”

Highland Park resident Miles Zaremski told the paper: “I heard 20 to 25 shots, which were in rapid succession. So it couldn’t have been just a handgun or a shotgun.”

CBS Chicago digital producer Elyssa Kaufman, who was watching the parade with her family, said that “everyone was running, hiding and screaming.”

“It was extremely terrifying,” she added. “It was very scary. We are very fortunate, we got out very quickly.”

Gun control advocates lamented the latest of more than 300 U.S. mass shootings this year.

“Another horrifying day in America,” tweeted anti-poverty activist Joe Sanberg. “We must do everything we can to end gun violence.”

Democratic Kentucky U.S. Senate candidate Charles Booker tweeted that “freedom to die at a holiday parade is not freedom,” while Ohio progressive Nina Turner asked, “What freedom do we have if we fear being gunned down at a parade?”

Separately, at least nine people were killed and scores more were wounded, with the injured ranging in age from 10 to 90, in Chicago shootings over the July 4th weekend.

Gun violence has been a problem across the US for years, drawing condemnation and calls for gun control, especially in the aftermath of mass shootings.

Those calls grew louder following a recent attack at Robb Elementary School in Uvalde, Texas, that killed 19 children and two teachers, and after a racist shooting at a grocery store in Buffalo, New York, left 10 Black people dead.

Late last month, President Joe Biden signed into law the first major federal gun reform in 30 years. The bill includes provisions to toughen background checks for the youngest gun buyers, keep firearms from more domestic violence offenders, and help states put in place red-flag laws that make it easier for authorities to take weapons from people deemed to be dangerous.

In a statement on the afternoon of the attack in Highland Park, Biden expressed shock at “the senseless gun violence that has yet again brought grief to an American community on this Independence Day.”