CHICAGO (WLS) -- If you're arriving at the O'Hare CTA Blue Line station between 10 p.m. and 4 a.m. you will have to show proof of airport business, the city said Friday.
That proof could be a boarding pass or an employee badge.
The Chicago Department of Aviation said in a statement, "In order to provide a secure environment at O'Hare International Airport, CDA security personnel work with the Chicago Police Department to enforce existing laws, which make clear that it is unlawful to be at Chicago's airports without any airport business."
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In February, Mayor Lori Lightfoot vowed to remove people experiencing homelessness from the airport, calling it a safety issue.
Advocates and workers say the number of unhoused people that sleep or take refuge at the airport has increased substantially this year.
As a secure location, O'Hare does not allow members of the public to be at the airport unless they are flying in or out or work there. Chicago police and the city Department of Aviation have said "we absolutely, fundamentally cannot have people sleeping in our airports who are homeless. That is unacceptable," the mayor said.
Haymarket Center's O'Hare Outreach program, which connects those experiencing homelessness and seeking shelter at the airport with resources, served 618 unhoused people at the airport in 2022 - up 58% from 2021, when it served 431. Haymarket had 14,000 interactions with the unhoused in 2022, which is up significantly from 2018, when 8,132 interactions were recorded with 392 people.
The Sun-Times Media Wire contributed to this report.