Editor's note: Four people who allegedly kidnapped and abused a mentally disabled man and streamed the attack on Facebook Live were charged on Jan. 5, 2016, with a hate crime and other charges. Full story here. (1:16 p.m.)

Chicago police say they are considering hate crime charges against four people shown in a Facebook video attacking a mentally disabled man, cutting his scalp with a knife and punching him while yelling obscenities about Donald Trump and "white people."

The 18-year-old man, who had been reported missing by his parents in Crystal Lake earlier this week, is shown crouching in a corner on a video carried on Facebook Live. His wrists are bound and his mouth is taped shut.

As a woman shoots the video, two men cut the man's shirt with knives, then take turns punching him and stomping his head. One of the men cuts the victim’s hair and scalp with a knife, and it appears the man is bleeding.

As the man crouches against a wall, someone shouts, “F‑‑‑ Donald Trump” and “F‑‑‑ white people.”

The attackers on the video appear to be black and the man appears to be white, though police declined at a news conference Wednesday evening to give the race of the attackers or the victim. The attack appears to have taken place on the West Side.

Area North Cmdr. Kevin Duffin said the department was considering hate crime charges but said it was not yet clear whether the attack was motivated by race.

“They’re young adults. And they make stupid decisions,” Duffin said. “That certainly will be part of whether or not we seek a hate crime to determine whether this is sincere or just stupid ranting and raving.”

Police Superintendent Eddie Johnson said hate crimes were a possibility.

"It's sickening. It makes you wonder what would make individuals treat somebody like that,” Johnson said. “I've been a cop for 28 years and I've seen things that you shouldn't see. It still amazes me how you still see things that you just shouldn't.

"I'm not going to say it shocked me but it was sickening," he said.

Police spokesman Anthony Guglielmi later said investigators believe the man was targeted because he had special needs, not because he was white.

However, police and prosecutors were still considering hate crime charges because of what was said on the video and because of the victim's disabilities, he said.

Chicago police condemn the "sickening" video of an attack on a tied-up man which was broadcast on Facebook. Jan. 4, 2017. (WGN-TV) Chicago police condemn the "sickening" video of an attack on a tied-up man which was broadcast on Facebook. Jan. 4, 2017. (WGN-TV)

The man was found wandering the streets in shorts Tuesday evening in the 3400 block of West Lexington Street in the Homan Square neighborhood, police said. Investigators believe he may have been attacked at a home about a block east from where he was found.

He had been reported missing Monday by his parents who said he disappeared after they dropped him off at a McDonald's in Streamwood on Saturday, according to police. The man apparently met someone he considered a friend, and then got involved with a group of people who stole a van from Streamwood.

Streamwood police said the parents began getting text messages from someone "claiming to be holding him captive." As Streamwood officers investigated the texts, they "discovered Facebook video depicting (the man) being verbally and physically abused."

Streamwood investigators were soon contacted by Chicago police saying they had found the man who had been reported missing, police said. Soon after that, officers were called to a home in the 3300 block of West Lexington about 5:25 p.m. and found signs of a struggle and property damage that they linked to the attack, according to police.

The man was "traumatized" and taken to a hospital. "After his treatment at the hospital, he was released and his parents came into (the) Area North Detective Division,” Duffin said.

The four people taken into custody, two men and two women, have given videotaped statements, Duffin said. Police haven't identified the individuals in custody, but said three are Chicago residents and one is from suburban Carpentersville.

The Cook County state's attorney’s office was interviewing the man and his family and charges were expected soon, police said.

Associated Press contributed to this report.