A sudden gust of strong wind turned the bluesfest at Indiana State Fair into a horror show by causing the concert stage to collapse and crush four people to death.

A few minutes before the coutry duo Sugarland was scheduled to take the stage and belt out blues, high winds began rocking the concert stage and, to everybody's horror, the steel beams buckled and the entire stage collapsed into a heap.

As the stage collapsed, thousands of people went scurrying for safety but everybody was not so lucky.

At the time of reporting, four people were reported dead and over 40 were left seriously injured.

An emergency medical team has been despatched to rescue and tend to the injured.

Indianapolis Metropolitan Police Department said the injured were being tended at Riley Hospital, Methodist Hospital of Indianapolis and Wishard Memorial Hospital.

The Indianapolis Department of Public Safety has launched a probe into the accident. The gusty winds that blew on Saturday registered speed up to 70 mph.

Concertgoers were warned of bad weather but nobody expected a thunderstorm and gusty winds to blow by as the Sugarland performance drew closer.

Everything happened in an instant without warning. When the stage collapsed, chaos ensued and screams pierced the air as the concertgoers scrambled for the exits. "We didn't expect this to happen. Some rain, yes. But none of us were prepared for the storm," said concertgoer Joe Hernandez. Joe was only 20 feet away from the stage when it collapsed. "It happened all of a sudden. The sky got black, suddenly there was this strong wind and the stage fell," he said.

One of the dead was a 7-year old boy who had come to watch the Sugarland duo.

The fair organizer said an announcer had reviewed safety and evacuation procedures for the concertgoers in case an emergency situation arose.

Sugarland singer-songwriters duo Jennifer Nettles and Kristian Bush, who were supposed to headline the bluesfest, were left shocked and extremely saddened by the incident. "“We are all right. We are praying for our fans, and the people of Indianapolis. We hope you'll join us. They need your strength," the duo tweeted.

Sara Bareilles, the evening’s other star performer, tweeted she was "safe" but left "speechless" by the incident.
"Fortunately we are all safe, but a tragic stage accident has injured some folks in indiana. Our prayers are with them and their families.

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

None of the performers were hurt by the accident. At the time of reporting, the fair organizer did not say whether future concerts will take place at the 17-day fair as scheduled. Janet Jackson is set to perform on Aug. 17, Train and Maroon 5 are scheduled for Aug. 18, and Lady Antebellum for Aug. 19.

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