Mayor Rahm Emanuel says the city is suing consumer reporting agency Equifax after last month’s massive breach that exposed 143 million consumers to possible identity theft—including 5.4 million Illinoisans.

Some 143 million Americans may have had personal information stolen in the cyberattack of credit-reporting company Equifax. What you need to do immediately.

Of Illinois’ 12.8 million residents, an estimated 5.4 million may have been impacted by the Equifax data breach. We review what you can do to protect yourself from potential identity fraud.