Police Chief Dan Thompson said that there was no evidence the bloodshed Sunday was a terrorist attack or that the suspect, Darrell Brooks Jr., knew anyone in the parade. Brooks acted alone, the chief said.
Brooks, 39, of Milwaukee, had left the site of the domestic disturbance before officers arrived, and was not being chased by police at the time of the crash, according to the chief, who gave no further details on the dispute.
Police said they were drawing up five charges of intentional homicide against Brooks.
He has been charged with crimes 16 times since 1999 and had two outstanding cases against him at the time of the parade disaster - including one in which he was accused of deliberately running down a woman with his vehicle.
On Sunday, a joyous scene of marching bands and children dancing in Santa hats and waving pompoms gave way in an instant to screams and the sight of crumpled bodies as the SUV sped through barricades and struck dancers, musicians and others in the community of 72,000.
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The dead were identified as four women ages 52 to 79 and an 81-year-old man. Members of a Dancing Grannies club were among those killed, as was a bank employee.
Mayor Shawn Reilly described the parade as a "Norman Rockwell-type" event that "became a nightmare."
"It looked like dummies being thrown in the air," said Nicole Schneiter, who was there with her children and grandchildren. "It took a second to register, like, 'Is that what we really just saw?' And then you looked in the road and there were just people laying in the road."
At least nine patients, most of them children, were listed in critical condition at two hospitals, and seven others were reported in serious condition.
Hundreds gathered at a downtown park Monday night for a candlelight vigil to honor those lost and hurt. Volunteers handed out sandwiches, hot chocolate and candles at the vigil, which was attended by interfaith leaders and elected officials.
"We are parents. We are neighbors. We are hurting. We are angry. We are sad. We are confused. We are thankful. We are all in this together. We are Waukesha Strong," said a tearful Amanda Medina Roddy with the Waukesha school district.
The chief said that while police were not pursuing Brooks before he entered the parade route, an officer did fire a shot to try to stop him but ceased shooting because of the danger to others. Brooks was not injured.
WATCH: Wisconsin parade survivor describes 'screams and chaos'
Brooks has two open criminal cases in Milwaukee County. In one case, filed Nov. 5, he is charged with resisting or obstructing an officer, reckless endangering, disorderly conduct, bail jumping and battery. Records show his $1,000 cash bond was posted on Friday.
In that case, a woman told police that Brooks deliberately ran her over with his vehicle in a gas station parking lot after a fight. She was hospitalized for her injuries.
In the other case, filed in July 2020, Brooks is charged with reckless endangering and illegal possession of a firearm.
His attorney in those cases, Joseph Domask, said he was not representing him in the parade crash.
The Milwaukee County District Attorney's Office said prosecutors' $1,000 bail recommendation for Brooks was "inappropriately low," given the charges. The DA's office said it is investigating the matter.
Republican Rebecca Kleefisch, a former Wisconsin lieutenant governor who is running for governor in 2022, called the killings "yet another avoidable tragedy that occurred because a violent career criminal was allowed to walk free and terrorize our community."
Brooks is an aspiring rapper. On a YouTube page, a video that has since been removed showed him rapping in front of a red Ford SUV resembling the one at the parade. The rapper uses the name MathBoi Fly on his Twitter and other social media accounts.
The horror of the crash was recorded by the city's livestream and onlookers' cellphones. One video shows the moment the SUV broke through the barricades and includes the apparent sound of gunfire.
"It was like a war scene walking through there" afterward, said Ken Walter, who had been riding in the parade in a hot air balloon basket towed on a trailer along with his wife and youngest son. "There were these piles of blankets with cops standing over them that you just knew were bodies."
Walter said he saw a red SUV careen into view and watched it hit a member of his real estate-agency parade contingent, then barrel straight into members of the Waukesha South High School marching band.
The SUV continued down the parade route. Behind it, people were screaming, running, searching for family and friends and unsure whether they were still in danger, he recalled.
Schneiter said that after sheltering in a store, she emerged to see bodies in the street, along with strollers, chairs, candy and shoes.
Police identified those killed as Virginia Sorenson, 79; LeAnna Owen, 71; Tamara Durand, 52; Jane Kulich, 52; and Wilhelm Hospel, 81.
The Milwaukee Dancing Grannies posted on its Facebook page that its members were "doing what they loved, performing in front of crowds in a parade, putting smiles on faces of all ages, filling them with joy and happiness."
Eighteen children ages 3 to 16 were brought to Children's Wisconsin Hospital, including three sets of siblings, said Dr. Amy Drendel, medical director of the emergency department.
They suffered injuries ranging from scrapes on their faces to broken bones and serious head injuries, she said. Six were listed in critical condition.
The Waukesha school district canceled classes Monday and Tuesday and said extra counselors would be on hand for students and staff. The parade's lineup included cheer, dance and band entries associated with district schools.
The parade, held each year on the Sunday before Thanksgiving, is sponsored by the Chamber of Commerce. This year's parade was the 59th one.
Waukesha is about 55 miles (90 kilometers) from Kenosha, where Kyle Rittenhouse was acquitted Friday of all charges in the shooting deaths of two men and the wounding of a third during unrest there in 2020.
This story has been corrected to show that online court records indicate a Darrell Brooks Jr. faces charges in another case that include second-degree recklessly endangering safety and that bail in a previous case was $1,000, not $500.
Bauer reported from Madison, Wis., and Balsamo reported from Washington. Associated Press writers Doug Glass in Minneapolis, Kathleen Foody in Chicago, Tammy Webber in Fenton, Michigan, Bernard Condon in New York and Michael Biesecker in Washington contributed.