Fourteen Backstreet Boys fans were injured outside a concert after severe weather caused a structure to collapse outside WinStar World Casino and Resort Saturday night, a spokesperson said.

At about 5:30 p.m. Saturday, a storm blew through Thackerville, Oklahoma with 70-80 mph winds and knocked over entrance trusses, injuring the fans, said WinStar spokesperson Kym Koch Thompson.

Hey folks! Severe weather, high winds and rain just passed thru here in Thackerville, OK. Emergency crews are on the seen as tent calapsed and some folks who were seeking shelter were injured. Waiting to determine damage to our stage and production. Status of show TBD. ✌🏻❤️ — Kevin Richardson (@kevinrichardson) August 18, 2018

Thompson said WinStar officials started to evacuate fans waiting to get into the outdoor concert venue at about 5 p.m. after lightning got within four miles of the casino.

All concertgoers were asked to move inside before the storm hit, but Thompson said about 150 people stayed in line for the show.

All 14 people who were injured were treated at the scene and then transported to area hospitals with minor injuries, Thompson said. All victims were later released.

Emergency personnel had to use a forklift to remove the metal sign from on top of people waiting in line at the @backstreetboys concert. #oknews #okwx #WinStarCasino #BackstreetBoys pic.twitter.com/jOcR18sffa — Sydney Stavinoha (@SydneyStavinoha) August 18, 2018

The show was ultimately canceled, and WinStar said tickets will be honored when the concert is rescheduled.

Editor's note: Winstar originally said the trusses supporting the structure were concrete. On Monday they told NBC 5the trusses were not made of concrete but that they could not confirm the metal or composite used in their construction.

