8-year-old boy identified as 6th fatality in Wisconsin Christmas parade

Darrell Brooks, the man accused of killing six and injuring 62 when his SUV plowed into a Christmas parade on Sunday, appeared to have "no emotion on his face" while doing so, according to a criminal complaint.

At one point an officer “pounded on the [suspect's] driver’s side door yelling ‘stop,’” the criminal complaint said.

But instead, according to the complaint, Brooks kept going, and later he "appeared to rapidly accelerate" and "took an abrupt left turn into the crowd of parade participants."

The SUV "appeared to be intentionally moving side to side, striking multiple people, and bodies and objects were flying," the complaint said.

One witness told police the suspect drove "in a zigzag motion," the complaint said. "It was like the SUV was trying to avoid vehicles, not people. There was no attempt made by the vehicle to stop, much less slow down.”

Another witness told police it appeared to be "a direct intent to hit as many parade participants," the complaint said.

A sixth person, a child, has died from injuries from the crash, a prosecutor said at the suspect's first court appearance.

The suspect, Darrell Brooks, is a registered sex offender in Nevada, where he was convicted in 2006 of impregnating a 15-year-old.

As a result of that conviction, Brooks was arrested 10 years later when he failed to obey sex offender laws. He bailed out on the charge but never returned to court, according to police in Sparks, Nevada. A warrant was issued on Aug. 15, 2016 for that failure to appear. 

-ABC News' Aaron Katersky

Darrell Brooks, the man suspected of plowing his car into the Christmas parade, is set to make his first court appearance at 5 p.m. ET Tuesday.

The initial charges against Brooks, 39, are five counts of first-degree intentional homicide.