Story highlights Texas man had surgery after suffering leg gash but is "doing fine," brother says

The multicar crash happens at the end of a Nationwide Series race in Daytona speedway

Debris, including an engine, ends up airborne -- some reaching the stands' second level

12 patients are at one hospital, two of them in critical but stable condition, official says

Debris flew into the stands, injuring a number of spectators -- at least two of them critically -- during a jaw-dropping crash Saturday in the final turn of a NASCAR race at Daytona International Speedway.

The multicar crash occurred near the end of the Nationwide Series Drive4COPD 300 race at the same Florida track where Sunday's Daytona 500 will be held.

The race had recently restarted after another wreck, after which driver Michael Annett was hospitalized for bruising to his chest, according to Richard Petty Motorsports.

Several closely-packed cars were jostling for position at top speed when they got tangled up, setting off a dangerous chain reaction that ensnared a number of vehicles.

Reigning Sprint Cup champ Brad Keselowski -- who later told CNN he and others were simply "going for the win" -- was among those involved, while Tony Stewart somehow emerged unscathed and finished by winning the race.

Driver Kyle Larson's vehicle ended up flying into a fence that separates the track from spectators. It broke into pieces -- including tires and a fiery engine.

Larson walked away from the crash, even after the front part of his No. 32 car was completely gone. He and the other nine drivers involved told reporters that they were checked at a medical tent on the Daytona infield and released.

Some of the shredded debris flew into the barrier, while others got into the stands -- some of it reaching the second level about 20 feet up.

video posted on YouTube shows a cloud of debris flying into stands and one man gasping, "Oh, my God." A tire rests on one seat, as a man frantically waves and yells to get the attention of paramedics.

Afterward, several spectators could be seen lying down after apparently suffering injuries. A line of about 10 ambulances lined up on the track, with some first responders carrying stretchers.

Fourteen fans were treated at an on-site medical facility, while 14 others were transported to area hospitals, speedway president Joie Chitwood told reporters.

"I'm just hoping everyone is OK," said Keselowski. "As drivers, we assume the risk. But fans do not."

NASCAR president Mike Helton earlier told ESPN, which was broadcasting the race, some people were taken to Halifax Health Medical Center. He said the protective fence did its job in preventing potentially more injuries and possibly deaths.

Byron Cogdell, a spokesman for the hospital, told CNN that his facility was treating 12 patients. Two of those -- one of them a child -- are in critical but stable condition.

"Everybody appears to be in stable condition," Cogdell said.

Staff at Florida Hospital Memorial Medical Center were treating one person and expecting three more, spokeswoman Lindsay Rew said Saturday evening.

The injured include Eddie Huckaby, a 53-year-old Krum, Texas, resident who suffered a leg gash when a large piece of metal hit him as he was watching the race, his brother Terry Huckaby told CNN affiliate WKMG . He described the motor landing in the stands, as well as a wheel "and everything flying over your head and debris everywhere."

"He's doing fine," Terry Huckaby said of his brother, who underwent surgery at Halifax Health Medical Center. "The first thing he said, 'I don't want to miss that (Daytona 500) race, but I have to watch on TV.'"

Accidents are nothing new to NASCAR, where cars often cruise at speeds topping 190 mph, nor to the Daytona track. One of the sport's most horrific, and well-known, wrecks happened in the 2001 Daytona 500, when famed driver Dale Earnhardt Sr. was killed -- also, on that race's final lap.

Still, injuries and fatalities to spectators are much rarer.

With the stands having been quickly evacuated, crews worked to repair the damaged fence. Chitwood expressed confidence the 55th edition of the Daytona 500 would go on as planned, with spectators even sitting in the same seats struck by debris Saturday.

"With the fence being prepared tonight to our safety protocols, we expect to go racing tomorrow with no changes," Chitwood said.