The attack happened on Halloween near an ice cream stand at Navy Pier. Miguel Morales, 20, says he suffered a concussion, eye injuries and numerous cuts and bruises when as many as seven people attacked him.
Morales says he was beaten after he tried to stop the alleged attackers from harassing his five younger siblings. He says one of them punched his 15-year-old sister in the face.
"It ended when I guess they heard the police come running, I guess, because the security guards were there. I noticed there were security guards. They didn't want to interfere, I guess because they didn't want to get hit with a chair. But I got hit a couple of times, more than seven times," said Morales.
Navy Pier officials say security guards were first on the scene and called police.
Officers arrested an 18-year-old and a juvenile. Both were charged with battery.