What we know about what happened at the Wisconsin Christmas parade

The celebratory sounds of a were interrupted by terrified screams Sunday after a vehicle plowed into participants and spectators gathered for the event in Waukesha, a city about 20 miles west of downtown Milwaukee.

At least five people were killed and more than 40 were injured in the chaos, said.

Here's what we know about the incident unfolded.

What happened during the parade

Crowds were bundled up along Waukesha's Main Street to enjoy the parade when a red SUV drove through a series of barricades and barreled onto the parade route around 4:39 p.m. local time, Waukesha Police Chief Daniel Thompson said.

A recorded by Angela O'Boyle, who was watching from her fifth-story apartment balcony, shows the SUV hitting an individual in a marching band. The vehicle then continues forward, hitting and running over others in the band and crowd before driving away.

In the video, people can be heard screaming and seen running for safety as the SUV continues its path through the crowd.

Video of the parade published on the city's shows a red SUV driving quickly through the parade, followed by a running police officer.

A Waukesha police officer discharged their weapon in an attempt to stop the driver, Thompson said. No bystanders were struck by the officer's gunfire, the chief added, noting he doesn't believe any shots were fired from the SUV.

A vehicle was recovered and a "person of interest" was taken into custody, Thompson said. "The scene is now safe," the chief said Sunday evening.

Officers and citizens took victims to the hospital in their personal vehicles, Thompson said Monday afternoon.

Where the investigation stands

The driver has been identified as , 39, of Milwaukee, Thompson said Monday afternoon at a news conference. He faces five charges of intentional homicide and more charges are possible.

The chief said no motive is known. Brooks was involved in a domestic disturbance earlier Sunday and left the scene just prior to driving his SUV through the parade, Thompson said.

"We are confident he acted alone," Thompson said. "There is no evidence this is a terrorist incident."

Thompson said the SUV was identified shortly after it ran through the parade and Brooks was quickly arrested. He was not injured, Thompson said.

Special Agents with the Bureau of Alcohol, Tobacco, Firearms and Explosives have responded to assist the Waukesha Police Department, according to Erik Longnecker, acting division chief of the Public Affairs Division of the ATF.

City Hall is closed to the public, although media will be allowed in for news conferences.

Who was injured and killed

The five deceased victims were identified on Monday as Virginia Sorenson, 79; LeAnna Owen, 71; Tamara Durand, 52; Jane Kulich, 52, and Wilhelm Hospel, 81.

Among the injured are , a Catholic priest, multiple parishioners and Waukesha Catholic school children, according to Sandra Peterson, the communication director for the Archdiocese of Milwaukee.

"Please join us in prayer for all those involved, their families, and those who are traumatized from witnessing the horrible scene," Peterson said .

Children's Wisconsin, a pediatric hospital in Milwaukee, received 18 injured children ranging in age from 3 to 16, Amy Drendel, director of the Emergency Department and Trauma Center, said in a news conference on Monday.

"Injuries ranged from facial abrasions to broken bones to serious head injuries. Six of these patients were sent to the operating room last night and two additional patients are undergoing surgeries today," Drendel said.

Three sets of siblings are among the patients, Drendel said.

As of Monday, two children were discharged from the hospital, said Dr. Michael Meyer, medical director for the hospital's pediatric intensive care unit.

CNN's Natasha Chen reported Monday 10 of the children were treated in intensive care.

CNN reported earlier that 15 patients total were being treated there.

Aurora Medical Center-Summit, a hospital in Waukesha County, told CNN Sunday night it was treating 13 patients: three listed in critical condition, four in serious condition and six in fair condition. "We are deeply saddened by today's senseless tragedy and our hearts are with the Waukesha community," a statement from the hospital said.

Froedtert Hospital in Milwaukee -- the only Level I trauma center in southeast Wisconsin -- treated seven patients, said Nalissa Wienke, senior media relations specialist for Froedtert & the Medical College of Wisconsin. Level I trauma centers typically care for the most critically ill patients.

The Milwaukee Dancing Grannies posted a statement on Facebook Monday, saying members of the group were among the dead in Sunday's tragedy in Waukesha, Wisconsin.

"Those who died were extremely passionate Grannies," according to

Their statement did not mention how many members of the group were involved in the incident.

The School District of Waukesha canceled classes through Tuesday, according to the district.

"The District will have additional counselors available during the school day at all buildings for all students that may be in need of support services," school officials said in a statement.

How witnesses described what happened

O'Boyle, who recorded the incident from her balcony, told CNN she was watching the parade when "the next thing I heard were screams, and turned my head and saw the car come and plow into the band that was just pass my balcony at that point.

"It hit at least two people right away and rolled over them. And then continued down the road to People's Park which is at the end of the block -- and then kept going, it didn't stop."

O'Boyle said she heard screaming and people yelling out their children's names, adding "it was not something that I wanted to see ... a little freaked out."

Angelito Tenorio, who is running for Wisconsin state treasurer and was campaigning at the parade, said the scene was "absolutely chaotic."

"Nobody knew if this was an attack or if this was an accident or if it was a deliberate attack on the people of the parade," he said in an interview with CNN. "People just started fleeing, running away from the scene, leaving behind their belongings, grabbing their children, calling, screaming, looking for their loved ones.

"And when the crowd cleared out, that's when it looked like I saw people, who appeared to be lying in the middle of the street, lying still, lying lifeless."

Kaylee Staral, a Milwaukee Journal Sentinel intern who also witnessed what happened, told CNN's Pamela Brown "probably around 20 to 30 minutes into the parade, a red SUV came running down the middle of the street -- there were a lot of screams -- and we almost thought maybe it was Santa, but it was a red SUV and it hit a lot of people."

Staral went on to say "there were multiple people on the ground."

In her description of what she saw, Staral said "right in front of me in the little spot where I was sitting, probably four people were down, so there were a lot of people that ran to go check on them. I believe that the four people in front of me were still breathing but they were down, they were not moving."

Biden offers prayers for the community

Speaking from the White House Monday, President Biden offered prayers for the community and called the parade incident a "horrific act of violence."

"While we don't have all the facts and details yet, we know this morning that five families in Waukesha are facing fresh grief of a life without a loved one. At least 40 Americans are suffering from injuries, some of them in critical condition, and an entire community is struggling, struggling to cope with the horrific act of violence," Biden said.

Wisconsin Governor Tony Evers (D) ordered all flags be flown at half-staff at "all buildings, grounds and military installations" across the state, to honor those who were killed and injured at the Waukesha parade, according to a statement released by the governor's office Monday.

"While much is still unknown, including the full extent of injuries and the number of lives lost" the statement added, "the people of Wisconsin pray for the Waukesha community and all those affected, and mourn the loss of life that occurred as a result of this senseless tragedy."

The-CNN-Wire