Evanston police investigate detention by federal agents of man who turned out to be U.S. citizen

Police in Evanston, Illinois, said they are investigating after federal agents allegedly tried to arrest the wrong man this past weekend.

Evanston police said at 9:49 a.m. Sunday, a caller reported hearing two men quarreling and someone stating that a person would be taken into custody.

Officers arrived at the scene on Howard Street between Dodge and Dewey avenues — or California and Washtenaw avenues on the Chicago side — and found a man on the ground with several people assisting him.

The man reported injuries to his head, neck, and teeth, police said. Witnesses told officers that agents they believed were from U.S. Immigration and Customs Enforcement had tried to take the man into custody.

Video from the scene showed agents holding the man down, and at times, it looks like the agents may have struck the man. Eventually, other people walk up to the man and offer him help.

Another Evanston police officer found two sport-utility vehicles at Dodge Avenue and Brummel Street, police said. A person in one vehicle, wearing plain clothes and a vest marked "POLICE" with federal law enforcement markings, said he was a federal agent conducting a fugitive investigation, police said.

The agent told police the man looked like another person for whom they were searching, and said the man refused to provide identification, police said. The agent said the man was detained for fingerprinting and resisted detention, police said.

Agents said they later realized the man was not the one for whom they were looking, and was a U.S. citizen, police said. The man was released.

The Evanston officer saw blood on the agent's hands, police said. The agent said he was injured while trying to handcuff the man, and declined medical treatment, police said.

The agent also told police five federal agents had been operating in separate vehicles in the area. He said the person they were seeking was associated with Chicago and had an arrest warrant out, police said.

The agent said federal agents left the area after protesters began to gather, in fear that the agents would be attacked, police said.

The man who was detained went to a local hospital, where Evanston police spoke with him and documented his injuries, police said.

CBS News Chicago has reached out to the U.S. Department of Homeland Security for comment.