Strong winds caused the collapse of a stage at the Indiana State Fair on Saturday night, killing four people and injuring at least 40, CNN reports. The powerful gust blew through around 9:00 PM after previously sunny skies had turned black and singer Sara Bareilles had finished her set. Sugarland was due onstage next, but the accident occurred before the duo could perform. Neither act was injured.

"I'm speechless and feel so helpless," Bareilles tweeted. "Please send love and prayers to Indianapolis tonight. My heart aches for the lives lost."

"We are all right," Sugarland tweeted. "We are praying for our fans, and the people of Indianapolis. We hope you'll join us. They need your strength."

The Indianapolis Star reports that police and fair executives were watching a big storm come in on the radar and made the call to evacuate the crowd. But just a minute later, a local radio executive took the stage to announce that the show would go on, warning the crowd to be prepared to evacuate mid-show if the weather got worse. But just before Sugarland were to play for the crowd of more than 12,000, the rigging above the stage came tumbling down, sending all of its massive lighting, sound equipment and one crew member who was working on the lighting crashing down.

"The gust of wind came, there was no rain yet and the production fell from left to right," music reporter David Lindquist told the Star. "You could clearly see people were under the footprint of the rigging."

Emergency crews rushed in to rescue people trapped under the rigging. Sadly, four died on the scene. Others were rescued in a matter of about 20 minutes, as fans helped workers pull their fellow concertgoers out from under the crashed rigging.

Both Bareilles and Sugarland scrapped plans to perform Sunday night at the Iowa State Fair.

Saturday's collapse is the third in a series of similar mishaps this summer. Last month, Cheap Trick narrowly avoided injury when a stage at Canada's Cisco Ottawa Bluesfest came tumbling down. Two weeks ago, rain and heavy wind in Tulsa, Oklahoma, brought down the Flaming Lips' lighting rig, preventing the band from playing an outdoor show at the city's District Block Party.

Rescue crews in Indiana worked throughout the night, and the American Red Cross set up a website where survivors can list themselves as "safe and well."

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