At least 14 people have been injured in Oklahoma after a strong storm knocked over the entrance trusses of an outdoor concert venue hosting 90's boy band favorites Backstreet Boys and 98 Degrees.<br /> Officials urged awaiting fans to seek shelter, but about 150 people ignored the warnings and continued to wait in line. <br />Saturday's concert was eventually cancelled and the Backstreet Boys said they will attempt to reschedule. <br />Two out of the 14 sent to hospital, meanwhile, have reportedly been released. <br />
