Organizers of the Firefly Music Festival asked fans to clear the festival grounds and seek shelter on Saturday night as severe weather conditions threatened the Woodlands in Dover, Del., reported NBC 10.

The Firefly Music Festival started in 2012 and has quickly gained recognition as the "East Coast's premier music festival experience," attracting thousands of concertgoers every summer.

Firefly organizers evacuated the festival grounds just before 10 p.m. as headliners Kings of Leon were about to perform on the main stage. An announcer's voice came over the loudspeaker and asked the fans to clear the festival grounds immediately due to inclement weather, according to The News Journal.

At 10:51 p.m. it started raining as thousands of fans were herded out of the grounds. Campers received alerts through the festival's mobile app to take down all pop-up tents and poles at their campsites. Some campers used the weight of their bodies to keep their tents from blowing away, while others headed out of the campsite altogether.

Rapper Kid Cudi's act had to be cut short after 20 minutes and performances of other artists such as Steve Aoki were also cancelled, according to Billboard.