A crash at the Daytona International Speedway today sent debris flying into the stands, injuring at least 17 fans, according to ESPN.

The exact number and nature of the injuries are not yet known, though officials at the Halifax Medical Center of Daytona Beach told reporters at least two of the injuries are critical.

The no. 32 car, driven by Kyle Larson, flew into the air in the midst of the 12-car crash just as the cars were angling to pass each other at the finish line. In footage of the race taken from the stands, pieces of the car can be seen smashing into and over the tall fence separating the racetrack from the stands. Spectators are heard yelling while others tend to what appears to be an injured fan.

Driver Tony Stewart won the race seconds later. The race, called the Nationwide Series Drive4COPD 300, precedes tomorrow's Daytona 500. At a press conference this afternoon, NASCAR officials told reporters tomorrow's race will go on and that crews are currently fixing the catch fencing around the track.