The glass ledge on a normal day. (Credit: Steven Baroncini)
NBC NEWS CHICAGO -- For those already afraid of heights, this story may cause some anxiety.
The Chicago Sun-Times reports that a glass enclosure known as "The Ledge" at the top of Willis Tower appeared to have cracked while people were standing on it Wednesday night.
A building spokesman told the Sun-Times that the crack was actually just a scratch-resistant coating, and not the glass itself. The spokesman said the coating is designed to do that and no one was in danger.
The Garibay family, of California, was on the glass at the time of the incident. Alejandro Garibay told NBC Chicago that when they heard the cracking they got off the glass and alerted staff.
NBC Chicago reported that all four ledges on the 103rd floor of the Willis Tower were closed Thursday while repairs were being made.
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