CHICAGO (Reuters) - Four African-Americans accused of attacking an 18-year-old disabled man on Facebook Live while making anti-white racial taunts pleaded not guilty in a Chicago courthouse on Friday.

File Photo: A combination photo shows four people charged with felonies for the beating of a man with mental health issues, L-R: Brittany Covington, 18, Jordan Hill, 18, Tanishia Covington, 24, and Tesfaye Cooper, 18, shown in Chicago Police Department photos released in Chicago, Illinois, U.S. January 5, 2017. Courtesy Chicago Police Department/Handout via REUTERS/File Photo

The attack on the man who authorities described as having “mental health challenges” drew international outrage after the video was widely shared on social media. The victim, who is white, was tied up for four or five hours, gagged and beaten, his scalp was cut and he was forced to drink toilet water, police said.

The four defendants were each charged with a hate crime, aggravated kidnapping, aggravated unlawful restraint and aggravated battery with a deadly weapon.

Jordan Hill, 18, Tesfaye Cooper, 18 and sisters Brittany Covington, 19, and Tanishia Covington, 24, have remained in jail since they were arrested for the Jan. 3 incident.

The victim’s family told authorities that they had received overwhelming support on social media. The incident also drew the attention of then-U.S. President Barack Obama, who called it “terrible” in an interview with Chicago’s ABC affiliate.

Police said the victim knew at least one of his accused tormentors, meeting Hill at a McDonald’s restaurant in a Chicago suburb during the last week of December.

Hill picked up the victim in a stolen van, police said. While the victim’s parents reported him missing, their son and Hill spent the next two days together, visiting friends and sleeping in the van.

On Jan. 3, a “play fight” between the two in the Covington sisters’ apartment escalated, police said.

In the video, the attackers could be heard making comments about “white people” as the victim cowered in a corner, his mouth taped shut.

At least one of the attackers could also be heard saying obscenities about Donald Trump, who was then president-elect. Police said they did not know whether the victim was a Trump supporter.

Alerted to the incident by neighbors who complained of noise coming from the apartment, police found the victim outside in freezing weather wearing only a tank top, shorts and sandals.

He was taken to a hospital and later released. Members of the public alerted investigators to the Facebook Live video.