A shooting at the end of the Kansas City Chiefs’ Super Bowl parade left at least eight people injured and sent terrified fans running for cover.

Fire Department battalion chief Michael Hopkins said eight to 10 people were injured but declined further comment, saying only that additional information would be released soon.

Police said in a news release that two people were detained. Fans were urged to leave the area as quickly as possible.

Lisa Money of Kansas City, was trying to gather some confetti near the end of the parade when she heard somebody yell “Down, down, everybody down”.

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Emergency personnel take a stretcher into Union Station (Reed Hoffmann/AP)

At first she thought somebody might be joking until she saw the Swat team jumping over the fence.

“I can’t believe it really happened. Who in their right mind would do something like this? This is supposed to be a day of celebration for everybody in the city and the surrounding area. and then you’ve got some idiot that wants to come along and do something like this,” she said.

Kansas City police tweeted that “child reunification stations” were set up at the main entrance to Union Station, and at 2301 Main St.

“We still have several needing reunification,” they said.

Police also asked witnesses to the shooting to go to a corner near Union Station.

Several people near the parade route were carried away on stretchers shortly after Chiefs fans marked their third Super Bowl title in five seasons.

Ofilio Martinez, 48, said he heard shots fired about 10 or 15 minutes before the gunfire near the Union Station rally.

“This is making me nervous, scared,” he said.

Kevin Sanders, 53, of Lenexa, Kansas, said he heard what sounded like fireworks and then people running back.

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Emergency crews arrive at the scene (Charlie Riedel/AP)

After that initial flurry, calm returned, and he did not think much of it. “We were sceptical,” he said.” But he said 10 minutes later, ambulances started arriving.

“It sucks that someone had to ruin the celebration, but we are in a big city,” Mr Sanders said.

Lisa Augustine, spokeswoman for Children’s Mercy Kansas City, said the hospital “is receiving patients from the rally”. She did not know how many or any details about their injuries.

The University of Kansas Health System was treating one person wounded in the shooting, said Jill Jensen Chadwick, news director for the health system.

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Several people were injured (Charlie Riedel/AP)

“When you have this many casualties, it’s going to get spread out among a lot of hospitals so that you don’t overwhelm one single ER,” she said.

Missouri governor Mike Parson and his wife were at the parade when shots were fired but are safe, Mr Parson tweeted.

“State law enforcement personnel are assisting local authorities in response efforts,” he said. “As we wait to learn more, our hearts go out to the victims.”

Chiefs’ trainer Rick Burkholder said he was with coach Andy Reid and other coaches and staff, and the team was on buses and returning to Arrowhead Stadium.

Areas that had been filled with crowds were empty after the shooting, with police and firefighters standing and talking behind an area restricted by yellow tape.

Central Kansas City in  Missouri had been a sea of red on Wednesday for Valentine’s Day as Chiefs fans celebrated their third Super Bowl title in five seasons with a parade.

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Police cordon off the area around Union Station (Reed Hoffmann/AP)

Confetti canons had exploded from double-decker buses as players rolled through the crowd, DJs and drummers heralding their arrival.

Crowds lined the route, with fans climbing trees and street poles, or standing on rooftops for a better view.

Owner Clark Hunt was on one of the buses, holding the Lombardi Trophy.

“Best fans in the world,” exclaimed wide receiver Mecole Hardman, who caught the winning touchdown pass, as he walked along the route, with the players signing jerseys and at least one person’s head.

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Police asked people to leave the area (Charlie Riedel/AP)

“Never stop,” running back Isiah Pacheco added from the route.

Key on the minds of many fans was whether pop superstar Taylor Swift would join her boyfriend Travis Kelce for the parade and victory speeches.

Swift has a show in Melbourne, Australia, on Friday, the first of three scheduled concerts on her Eras Tour.

She was nowhere to be seen early in the parade. Instead, Kelce was joined by his mother, Donna Kelce.