It's race weekend in Daytona. It should be a fun weekend! The annual Daytona 500 is on Sunday, and it's the biggest race of the year. But a scary crash at the finish of a Nationwide race on Saturday is hanging a dark cloud over the weekend's festivities. As the cars were coming around the race's final turn, and just moments before they were to cross the finish line, two cars bumped each other. They were both at the front of the pack racing towards the finish. One car lost control, spun around and into the other cars racing towards it. At least 13 cars were involved. The end result saw the car driven by 20-year-old Kyle Larson fly into the metal safety fence separating the race cars from spectators. The front half of Larson's car was completely ripped off. The rest of it ended up in the grass at the center of the track. Amazingly, Larson walked away unharmed. 

But the same can't be said for some of the spectators. As you can see in the video above, the crowds around the fence were packed to see the end of the race. Larson's car and engine ended up smashing into the fence. The engine managed to puncture it. USA Today's Jeff Gluck has been tweeting updates live from the race track. He compared hearing the crash live to a bomb going off. At least five spectators were taken away on backboards by medics. There seems to be spectators injured in the upper deck of the stands, too. One fan was able to snap this picture of a tire that flew into the upper part of the stands: 

This is a stream of ambulances leaving the racetrack: 

And this USA Today photo perfectly captured the moment Larson's car flew into the fence. 

Details are still coming in and we'll update this space as we hear more. 

Update 5:15 p.m.: Yahoo!'s Nick Bromberg paints a scary picture of some of the damage in the stands: 

A track worker told Yahoo! Sports that one woman had a tourniquet on her leg, others suffered burns and a tire landed on one fan when a multiple-car accident unfolded as drivers raced for the finish line in the final lap of the Drive4COPD 300.

Bromberg also reports there were at least six fans injured in the crash.

Update 6:10 p.m.: ESPN and Central Florida News report at least 17 spectators were transported to local hospitals after the crash; two with "major" injuries. At least one person is in critical condition.  One is heading into surgery for "head trauma." There was eyewitness video posted to Youtube taken a few feet away from where the tire (pictured above) landed in the stands, but somehow NASCAR was able to get Youtube to take the video down for copyright reasons. 

Update 6:12 p.m.: Deadspin has a copy of the fan video NASCAR had taken down from Youtube. Scroll to the very bottom. 

Update 6:30 p.m.: At least one person who was in critical condition is now in stable condition. 15 injured spectators were taken to one hospital and they're all now in stable condition.