Updated 11:50a to reflect identity.
Authorities have now identified the Country Thunder festival-goer who appears to have been struck by a lightning bolt overnight as a 22 year-old Illinois woman, Brittney Prehn.
Prehn had no identification and was unconscious when authorities responded just after 12:30 Friday morning.
She's being treated for serious injuries at Northern Illinois Medical Center, according to a news release from the Kenosha County Sheriff's Dept. Her condition wasn't disclosed.
Thursday was the first day of the four-day festival, which attracts thousands, many of whom camp out on the the festival grounds near Twin Lakes.