Country duo Sugarland scrapped a planned performance at an outdoor event in Iowa on Sunday after watching in horror as five people were crushed to death at the Indiana State Fair on Saturday.
The tragedy occurred when a powerful storm ripped through the fairground, causing stage scaffolding and light rigging to crash to the ground shortly before the band was due to perform.
Initial reports claimed four people had been killed in the disaster, but the number of fatalities has since crept up to five, while at least 48 other people were injured.
Sunday's schedule for the Indiana State Fair, which is due to continue until August 21, was axed as authorities continued the rescue mission to free those trapped under the heavy stage equipment.
Sugarland, who were due to headline the festivities, took to Twitter immediately after the terrifying accident to assure fans they were safe and ask devotees to pray for "the people of Indianapolis."
And they've been left so shaken by the Indiana tragedy, the country stars have pulled out of a similar slot at the Iowa State Fair, which was due to take place on Sunday.
Singer Jennifer Nettles tells the Associated Press, "There are no words to process a moment of this magnitude and gravity."
Meanwhile, pop star Sara Bareilles, who had performed at the Indiana State Fair earlier on Saturday, admits she is still in shock at the incident.
In a tweet to fans on Sunday, she writes, "I'm still thinking of all those affected from last night's stage collapse. My heart is here in Indiana. :( #prayforIndy"