The Shedd Aquarium was evacuated Thursday afternoon following a power outage.
The power went out about 1 p.m., according to Shedd spokeswoman Andrea Smalec, who said the outage is believed to be related to the heat.
The temperature at Northerly Island was 101 at 1 p.m., according to the National Weather Service.
"As a safety precaution all visitors have been evacuated," she said.
The Shedd’s full-time inhabitants appear safe, said Smalec, adding that back-up generators for "life-support systems are running full speed."
Commonwealth Edison spokeswoman Krissy Posey confirmed the outage, but said it was unknown if it was a ComEd failure or a Shedd system failure.
The utility is investigating and was also sending a generator in case it is needed.
It was unknown how long the power would be off or if the aquarium would re-open Thursday, Smalec said.
All guests who were evacuated received "come back" tickets, she said.
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