It started as a Kansas City Chiefs celebration. Then the message spread: ‘Guns, police, run’

The conquering heroes had just rolled down Grand Boulevard, waving to a crowd packed more than a dozen deep – a sea of red, gold and white against a clear blue sky, celebrating their Kansas City Chiefs’ second-in-a-row Super Bowl victory.

One after another, double-decker buses and open-topped SUVs had ferried the likes of championship MVP Patrick Mahomes, star tight end Travis Kelce and head coach Andy Reid, along with other coaches, relatives and mascots, down the iconic thoroughfare as some 1 million fans – among them countless kids who’d gotten the day off school – cheered.

Some Chiefs players at points had left their rides to walk the parade route, high-fiving supporters and posing for selfies. There Wednesday on the streets, too, were hundreds of police officers, many with chests puffed out by protective vests.

Like at most major public events, they scanned for trouble.

Soon, the Chiefs entourage arrived at Union Station, the century-old beaux-arts behemoth where all five World War I Allied commanders once arrived by train. Onto a stage set up for the NFL rally, Kansas City’s modern gridiron warriors hoisted the spoils of their latest, historic battle: the sterling silver Vince Lombardi Trophy, now glinting in the sun.

From above the crowd, the players and coaches hailed their legion of fans. They hugged and sang. They basked in their glory while revelers held cell phones aloft on video mode.

As confetti flew in the official festivities’ final moments, Jacob Gooch Sr. – there in the vast crowd with his wife, daughter and son – overheard an altercation, he told CBS.

“A girl” told someone: “Don’t do it, not here, this is stupid,” he said.

Then, Gooch’s wife and daughter saw a lady “holding (someone) back,” he recalled to the network.

And they saw a gun get drawn.

“People had started backing up, and then he pulled it out,” Gooch told CBS, “and just started shooting and spinning in a circle.”

In the main stage area, Manny Abarca and his 5-year-old daughter heard the screams.

A flood of people rushed toward them as, through the crowd, a warning quickly spread:

“Guns, police, run,” Abarca, a Jackson County legislator, later would tell CNN’s Laura Coates.

The mayor, at Union Station, also “heard something.”

“A number of us start running,” Quinton Lucas later recalled, “and I see a stream of officers going in (the) exact other direction with guns drawn.”

Madison Anderes, 24 – in the crowd with her brother and mother – heard what sounded like fireworks going off, she told CNN.

“He’s got a gun!” somebody yelled. “He’s got a gun!”

A second round of pops went off – this time much louder.

“That’s when all chaos broke out,” she said.

Everyone started running.

Anderes got knocked to the ground – and “felt like I was going to die.”

“I felt like a sitting duck,” she said, “and I was going to get shot.”

Abarca watched people get trampled in the chaos.

He picked up his daughter – and ran.

‘Stop this guy!’

Gooch was hit in the ankle, he told CBS. His son got hit, too, and so did his wife – a bullet piercing straight through her calf.

Radio DJ Lisa Lopez-Galvan also was shot, the station where she volunteered, KKFI 90.1 FM, later said. Her relatives, including two nieces and a nephew, were injured, according to the mayor of suburban Lee’s Summit, where her brother is mayor pro tempore.

A shooter took off on foot.

“Instinctually, I just took off running after him,” rallygoer Tony told CNN. “He was hopping barriers, I was hopping barriers, just trying to stay in somewhat distance of him and that way I could see a cop and identify that was the guy.”

Amid the fleeing crowd, Paul Contreras – at the Chiefs rally with his daughters – saw someone moving “in the opposite direction,” he told CNN’s Erin Burnett on Wednesday.

“Stop this guy!” somebody yelled.

Contreras just had the right angle, he said, and hit the person from behind, then tackled him.

“You don’t think about it,” Contreras said. “It’s just a reaction,”

A gun fell to the ground, he said.

Two others in the crowd quickly stepped in, leaning all their weight to help hold the person down.

But, Contreras said, he kept struggling to get away.

‘Don’t answer the phone, don’t make noise’

Also on the ground somewhere nearby, Anderes managed to get up and run with her brother and mother to a storefront, where about 10 others were huddling, she said.

Elsewhere, Chiefs offensive lineman Trey Smith was looking for cover in the crowded chaos zone, he told ABC News.

“There’s, like, a little kid in front of me, so I just grabbed him, just yanked him, was telling him, ‘You’re hopping in here with me, buddy,’” Smith said of the moment they joined 20 or so others in a closet.

Abarca, with his 5-year-old, found shelter in a nearby restaurant with Kansas City Chiefs players, owners, family members and Reid, the Chiefs head coach, he said.

His little girl, he said, went into “protocol mode,” telling her dad, “This is like training.”

“It broke my heart to think about the reality that my daughter knows what this is,” he told CNN’s Coates later as he decried the routine nature in US schools of active shooter drills.

Abarca’s wife soon called him as news spread of the gunfire at the Chiefs celebration.

But Abarca couldn’t answer.

“Because this is the protocol,” he said: “Don’t answer the phone, don’t make noise.”

His phone battery depleting, Abarca, too, was desperate for more information about what was happening outside the bathroom where he and his child were sheltering.

He scrolled through X for new details, he said – and frantically tried to return his wife’s texts.

Law enforcement, all the while, rushed toward the danger.

‘No one’s gonna hurt you’

Officers blitzed the crowd, including the spot Contreras and the other good Samaritans were pinning the stranger to the ground – the gun lying nearby.

“He was fighting the whole time,” Contreras told CNN. “And we were fighting him to keep him down.”

Police soon arrived and handcuffed the person, he said.

By the time the gunfire ended, radio DJ Lopez-Galvan was dead, her station and Abarca said, with police confirming a 43-year-old woman died. Another 22 victims – ages 8 to 47 – had been shot, Chief Stacey Graves said, adding half are younger than 16.

It wasn’t immediately clear if the person Contreras said he tackled was among the three people – two of them juveniles – Kansas City police detained after the shooting, which stemmed from a personal dispute, Graves said. An unspecified number of guns were recovered, she said.

And just like that, the street so recently packed by Chiefs fans eager to share in their team’s historic joy lay strewn with the empty coffee cups, discarded folding chairs and abandoned bags indicative of yet another mass shooting in America.

As unwitting survivors emerged from their hiding places, Smith stepped out of the closet still clutching the World Wrestling Entertainment championship belt he’d held as a prop through the Super Bowl parade and headed for the team buses, he told ABC News.

On the way, he noticed a small boy who was “hysterical.”

Hoping to calm the child’s nerves, Smith handed him the belt, and the two started talking about wrestling, he told ABC News.

“‘Hey, buddy, you’re the champion,’” Smith said. “‘No one’s gonna hurt you. No one’s gonna hurt you, man. We got your back.’”

Abarca, still with his 5-year-old, “will never forget finally coming out of the bathroom after hiding, sitting in the hallway,” he recalled to “CNN This Morning” on Thursday.

Then, around the corner walked Reid with his grandchildren and his wife.

The men’s eyes met, Abarca said, “and I think we knew what we were saying to each other.”

The head coach asked: “Are you guys OK?”

It was a moment of humility, Abarca said.

“That is the sentiment that is Kansas City,” he said. “It encompasses who we are.”

Now, the hometown of rare back-to-back Super Bowl champs is left to muster its strength as it faces a kind of horror more common across the United States every day, from churches and schools to grocery stores, outlet malls and hospitals.

“People … responded absolutely immediately,” the mayor said of the gunfire at the Chiefs rally. “But I wish that we lived in a world where they wouldn’t have to do that.”

“It seems,” Lucas said, “like almost nothing is safe.”

Correction: A previous version of this story incorrectly described Lisa Lopez-Galvan’s relationship with KKFI 90.1 FM. She was a volunteer there.

CNN’s Dakin Andone, Nouran Salahieh, Jamiel Lynch, Jillian Sykes, Kyle Feldscher, Matias Grez, Amanda Jackson, Raja Razek, Sarah Dewberry, Hannah Rabinowitz, Holmes Lybrand, Sara Smart, Chris Boyette, Shimon Prokupecz, Josh Campbell and Rebekah Riess contributed to this report.

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