Joseph L. Quinn, 46, yelled at George and carried a sign demanding that the cardinal step down, George told the communications director for the archdiocese.
Police said the man had been warned against entering the church, but went inside anyway and created a disturbance. Police said they did not find either a knife or a sign, the Chicago Tribune reported.
Quinn's mother, who lives on the South Side of Chicago, said she hadn't seen him in more than a year.
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