The red SUV slammed into families who had lined the streets for the Christmas parade in Waukesha, Wisconsin, injuring more than 40 people.
According to reports, an SUV driver was fleeing the scene of another crime when he ploughed into a Christmas procession, killing five people.
Crowds had gathered in Waukesha, Wisconsin on Sunday for the festive celebration when the tragedy occurred.
Over 40 people were hurt when the red truck careered through a crowd of families lining the streets.
According to a law enforcement official, it appeared as though the suspect was fleeing another event – potentially a knife fight.
The source also told the news outlet that, “at this time”, the incident does not appear to be an act of terrorism.
The suspect, who remains in custody, has not been named and a motive is yet to be revealed.
Waukesha Police Chief Dan Thompson said a vehicle had been recovered after the incident in the town, about 20 miles (32 km) west of Milwaukee.
“At this time, we can confirm that 5 people are deceased and over 40 are injured,” the Waukesha Police Department said on its Facebook page.
“However, these numbers may change as we collect additional information. Many people have self-transported to area hospitals.”
A video posted online showed a vehicle driving at speed through the parade, appearing to run over more than a dozen people before crowds ran from sidewalks to offer assistance.
Thompson said an officer fired shots at the vehicle and no bystanders were injured.
Police did not believe shots had been fired from the vehicle, he added, contrary to earlier reports.
Video on social media appeared to show police firing on the vehicle as it crashed through street barriers.
Belen Santamaria, her husband, and their three-year old daughter were planning to join the parade with their Catholic Church.
“The SUV came by at full speed,” said Santamaria, 39. “Then I started to hear people screaming.”
She hid in a restaurant with their daughter while her husband Jesus Ochoa, also 39, ran ahead to try to help injured people.
“I was going to be there, walking,” Santamaria said. “The SUV would have hit us too.”
A woman told Milwaukee’s Fox6 TV station that the SUV hit a dance team of girls between 9 and 15 years old.
She said the immediate reaction was silence, followed by screaming, running and checking on those injured, Fox6 reported.
Video on social media showed small groups surrounding injured girls with white pompoms scattered around.
One witness said the driver also hit a group of “Dancing Grannies” and at least one person flipped over the hood of the SUV, according to Milwaukee’s WISN-TV, an ABC affiliate.
“Members of the group and volunteers were impacted and we are waiting for word on their conditions,” the Milwaukee Dancing Grannies said on their Facebook page.
“Please keep the Grannies, all those injured, and all those who witnessed this horrible event in your thoughts and prayers.”
Another witness estimated the SUV was going about 40 mph (64 kph) when it hit the crowd parading down the street, the TV station said.
President Joe Biden was briefed by aides about the events, a White House official said.
Photos and videos of Waukesha circulating on Twitter showed police cars and ambulances crowding a street decked out with Christmas lights in the aftermath of the incident, which occurred around 4:39 p.m local time.