Just before 8:30 p.m., Chicago police confirmed they were responding to the hotel at 401 North Wabash Avenue in River North.
CPD said a SWAT team responded after a firearm was found inside a room at the hotel.
Responding officers took one person into custody without incident and recovered the gun.
Police said the investigation is ongoing and did not immediately provide further information.
Former President Donald Trump is not in Chicago on Tuesday night and has no plans to be in the city this week.
Additional details were not immediately available.