An investigation is currently underway into what exactly led to the abrupt end of the Rascal Flatts concert Thursday (Aug. 9) at the Ruoff Home Mortgage Music Center just outside of Indianapolis.

Toward the end of the concert, fans of the country band were told to evacuate the venue due to an unspecified security concern, leaving many not only confused, but disappointed.

"Everyone boo’d," concertgoer Britni Sherlock tells the Indy Star about the moment when an announcement came over the loudspeaker that the show was over. "We continued to wait in the pavilion, and that’s when security came up to everyone and told us to leave. I asked what was going on and he replied, 'We were told to evacuate the pavilion immediately.' "

One of the fans attending the concert captured video of the confusion that ensued. In the clip, the piano player plays a short snippet of the next song before stopping abruptly:

Hours after the security scare, Rascal Flatts’ Jay DeMarcus headed to his Twitter page to share a message with the disappointed fans.

“Indianapolis, Due to a security concern at the show last night, standard procedures were quickly executed and everyone was able to safely leave the building,” he writes along with the hashtag #backsoon. “The safety of our fans, band and crew is always the top priority for us, sorry for anyone that was disappointed."

Security scares are becoming increasingly common, and fears remain high as we approach the one-year anniversary of the Route 91 Harvest Festival mass shooting. Just last month, the Avett Brothers were forced to shut down their show after a man walked into the venue with a gun.

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