The man was in a business about 2 a.m. in the 600-block of North Wabash Avenue downtown Chicago, police said.
Bally's Chicago casino is on that block, and said in a statement they were made aware early Monday morning of a "security-related incident" that took place on their property.
CPD said two male suspects approached the victim, beat him up and took his belongings by force.
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The suspects left the scene. No one is in custody, police said.
The man "self-treated" his injuries, police said.
Area Three detectives are investigating.
"The safety and well-being of our guests, team members, and community remain our top priority. Upon becoming aware of the situation, the Bally's security team responded immediately and worked closely with local law enforcement and regulators to address the matter and identify the culprits," the statement said.
Bally's said there is no ongoing threat to guests or employees, and operations continue as normal.
"Bally's remains committed to maintaining a safe and secure environment and will continue to review and enhance our security procedures as appropriate," Bally's said.
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