Shortly after the "King of Anything" singer finished her opening set for country duo Sugarland, a gust of wind brought down the stage and its rigging.
"The weather changed in a matter of minutes and the stage collapsed in a matter of seconds," Bareilles explained. "We are shocked and saddened by this horribly tragic circumstance and we are all praying for those affected. The emergency response was incredibly speedy and the people of Indiana as well as the crews from the show were beyond brave and working hard to help each other."
"We're all right," they wrote. "We are praying for our fans, and the people of Indianapolis. We hope you'll join us. They need your strength."
In light of the fatal stage collapse, Bareilles and Sugarland have canceled their concert at the Iowa State Fair Sunday. The Indiana State Fair is scheduled to reopen Monday with a memorial service at 9 a.m.