KANSAS CITY, Mo. >> The mass shooting that unfolded amid throngs of people at the Kansas City Chiefs’ Super Bowl celebration, killing one person and wounding almost two dozen others, appeared to stem from a dispute between several people, authorities said today.

Police Chief Stacey Graves said the 22 people injured Wednesday ranged between 8 and 47 years old, with half under 16. A mother of two was killed.

Police said they detained three juveniles but released one who they determined wasn’t involved in the shooting, leaving two in custody. No charges have been filed. Police are looking for others who may have been involved and are calling for witnesses, victims and people with cellphone video of the violence to call a dedicated hotline.

“We are working to determine the involvement of others. And it should be noted we have recovered several firearms. This incident is still a very active investigation,” Graves said at a news conference.

The shooting outside Union Station occurred despite the presence of more than 800 police officers who were in the building and area, including on top of nearby structures, said Mayor Quinton Lucas, who attended with his wife and mother and ran for safety when the shots were fired. But he doesn’t expect to cancel the upcoming St. Patrick’s Day parade.

“We have parades all the time. I don’t think they’ll end. Certainly we recognized the public safety challenges and issues that relate to them,” Lucas said.

Wednesday’s celebration was the third such parade since 2020, and the others had no violence.

People packed the parade route, with fans climbing trees and street poles for a better view. Players rolled through on double-decker buses as DJs and drummers heralded their arrival.

Video taken from a building overlooking the celebration shows thousands of fans clad in red Chiefs gear milling about in a park in front of Union Station. As shots ring out and repeat, they suddenly scatter amid screams.

Some of those who flee return to help people on a street, sidewalk and grassy area. People nearby continue to scatter frantically even after the gunfire stops, but fans farther away remain, apparently not sure of what has happened.

The police chief said 1 million people likely attended the parade, which occurred in a city of about 470,000 people and a metropolitan area of about 2 million, but stressed that the violence was wrought by just a handful of people.

“The law enforcement response was exemplary. Those in attendance also responded,” Graves added.

Among them was Trey Filter, who was walking to the car with his family when he heard yells of “get him.”

Filter, 40, saw a fleeing person, prompting him and another bystander to try to tackle him. Filter eventually jumped on top of the person.

“I don’t know what the hell I was thinking,” the owner of an asphalt and concrete company recalled. “We was like, ‘We got him.’ I’ll always remember that. And then they started screaming, ‘There’s a gun!’”

The gun fell near his wife, Casey Filter, who picked it up. At that point the fleeing person was under a dogpile about 10 feet (3 meters) away.

Trey Filter, who lives outside Wichita, Kansas, was still processing the melee Thursday. But he was glad there wasn’t more carnage.

“I’m sure there were a thousand other men there that would have done it,” he said.

Police didn’t identify Filter as a man who intervened or specifically say whether the person he tackled was a suspect.

Wednesday’s rally had just ended and music was still blaring when the shots erupted. Many people initially thought they were hearing fireworks. But then chaos ensued. Some in the crowd hit the ground while others leapt over barriers and sprinted, some carrying children in their arms.

The crowd was so massive that normalcy returned quickly, with some unsure what had happened. But then ambulances arrived, and officers rushed in with guns drawn. Some of the less seriously injured were driven away on golf carts.

The stunned crowd — some in tears — slowly gathered their belongings, trying to figure out how to get home. Strangers comforted each other as police put up crime scene tape where moments earlier there had been a joyous celebration.

Hank Hunter, a Kansas high school sophomore, said he heard shots in the distance while watching the rally with a friend. Initially, they didn’t know what it was, but then, “like a chain reaction,” people started hitting the ground.

They ran to jump over a barricade, and his friend slammed his head into the concrete, Hunter said. A security guard ushered his friend into Union Station, which was closed to the general public, as the Chiefs players and coaches prepared to leave on buses. There, coach Andy Reid consoled his friend and “just tried to comfort him and calm him down.”

One video of the shooting’s aftermath that was posted on social media showed someone apparently performing chest compressions on a victim as another, seemingly writhing in pain, lay on the ground nearby. People screamed in the background.

The slain woman was identified by radio station KKFI-FM as Lisa Lopez-Galvan, host of “Taste of Tejano.”

Lopez-Galvan, whose DJ name was “Lisa G,” was an extrovert and devoted mother from a prominent Latino family in the area, said Rosa Izurieta and Martha Ramirez, two childhood friends who worked with her at a staffing company.

“She’s the type of person who would jump in front of a bullet for anybody — that would be Lisa,” Izurieta said.

Kansas City has long struggled with gun violence, and in 2020 it was among nine cities targeted by the U.S. Justice Department in an effort to crack down on violent crime. In 2023, the city matched a record with 182 homicides, most of which involved guns.

Lucas has joined with mayors across the country in calling for new laws to reduce gun violence, including mandating universal background checks.

University Health Truman Medical Center reported that three people with gunshot wounds were still being treated there Thursday, including two in critical condition. One was a man who survived only because staff got him to the operating room within five minutes of arrival, Dr. Dustin Neel said.

St. Luke’s Hospital spokesperson Emily Hohenberg said one gunshot victim was upgraded from critical to serious condition.

Children’s Mercy Kansas City said three children remained there. It had received 11 children ages 6 to 15, nine of whom were shot. All were expected to recover.

Stephanie Meyer, the hospital’s chief nursing officer, said Thursday that the children are scared and will need mental health support. The hospital’s staff members are also struggling.

“They’re struggling just like you and I are, and unbelievably heartbroken that this has happened in our backyard,” said Dr. Stephanie Burrus, the hospital’s chief wellbeing officer. “And we all train for this, we’re all prepared to take care of these children. But it doesn’t negate the fact that it’s still not normal for people to see many, many people wounded by gunshots.”

Associated Press writers Scott McFetridge in Des Moines, Iowa; Jim Salter in St. Louis; Josh Funk in Omaha, Nebraska; Summer Ballentine in Columbia, Missouri; and John Hanna in Topeka, Kansas, contributed to this report.