Dozens were hurt during the chaos in Waukesha.
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An SUV crashed through a Christmas parade in the town of Waukesha, Wisconsin on Sunday afternoon, hitting dozens of people and leaving five dead.
"Today our community faced horror and tragedy in what should have been a community celebration," Mayor Shawn Reilly said in a statement on Sunday night.
Police say they've arrested the driver but the person's identity wasn't immediately released. They also didn't say anything about a potential motive.
Witnesses said it was a terrifying experience to see the SUV drive through the crowd.
"It was the worst thing I've ever seen in my life," Tyler Kotlarek, 28, told the New York Times.
"He was going from side to side, targeting people," Kotlarek said. "He was flying through there going intentionally from left to right."
The City of Waukesha live-streamed the parade on its Facebook page, and the video shows the SUV speeding down the parade route. A few screams can be heard as it passes.
"We heard a loud bang," witness Angelito Tenorio told the Associated Press. "And after that, we just heard deafening cries and screams from the crowd, from the people at the parade. And people started rushing, running away with tears in their eyes, crying."
Chris Germain, who was driving a float in the parade, says the SUV "blazed right past us" and that an officer was running along after it.
The victims were not immediately identified but some of them belonged to a group called the Dancing Grannies, the AP reports.
Police are investigating the case and an update is expected on Monday afternoon.