An unidentified number of NASCAR fans were injured Saturday when debris from a wild crash on the last lap of the Nationwide Series season opener was sent flying into the grandstands at Daytona International Speedway.

Rescue workers attended to the injured in the stands. NASCAR officials did not disclose the number or severity of the injuries, but it was readily apparent that a number of fans were injured when a last-lap melee erupted in front of the grandstands on the front stretch when the No. 32 Chevrolet of rookie driver Kyle Larsen helicoptered into the catch fence, which sheared the front-end suspension and engine.

Kyle Larson, left, slid to a stop near Regan Smith after the wreck. A tire from Larsen’s car landed nine rows up in the grandstands near the start-finish line at Daytona’s 2.5-mile, tri-oval.

“We’ve always known since racing started that it’s a dangerous sport,’’ said winner Tony Stewart, who eluded the last-lap carnage that was triggered when race leader Regan Smith tried to block Brad Keselowski. “It’s hard and we assume that risk, but it’s hard when fans get caught up in it.’’

NASCAR driver Tony Stewart avoided a crash on the last lap to win the NASCAR Nationwide Series DRIVE4COPD 300 race at the Daytona International Speedway in Daytona Beach, Fla. The incident cast a pall on Stewart’s Victory Lane celebration, as the NASCAR Sprint Cup driver won the Nationwide Series season opener for the seventh time in his career and fifth time in the last six races.

Medical officials removed an injured fan from the stands following the incident.

NASCAR drivers crashed in an eleven car pile-up late in the NASCAR Nationwide Series DRIVE4COPD 300 race.

“So as much as we want to celebrate right now and as much as this is a big deal to us, I’m more worried about the drivers and the fans in the stands right now,’’ Tony Stewart said. “I could see it all in the mirror and it didn’t look good from our side.’’

Kyle Larson, driver of the Clorox Chevrolet, and Regan Smith, driver of the Clean Coal Chevrolet, crashed in front of fans.

An injured spectator was transported by emergency personnel.

Driver Kyle Larson climbed out of his car as Trevor Bayne rolled past.

Rescue workers attended to the injured.

Pieces of Kyle Larson's car flew through the air as he slid down the front stretch.

Medical officials removed an injured fan from the stands.

Kyle Larson was airborne after the multi-car crash, including Parker Kilgerman, Justin Allgaier and Brian Scott.

Medical officials removed an injured fan from the stands.

Kyle Larson slid along the wall after hitting the catch fence as Eric McClure went low.

Injured spectators were treated after the crash.

Emergency officials put out a fire from driver Kyle Larson's engine after his car hit the wall and safety fence along the front grandstands.

Driver Kyle Larson stood outside his car, missing the engine, after hitting the wall and safety fence.

Injured spectators were treated after the crash.

The No. 32 Clorox Chevrolet, driven by Kyle Larson, was in bad shape after the race.

An injured spectator was treated after a crash at the conclusion of the NASCAR Nationwide Series auto race.

Brad Keselowski and Kyle Larson slid across the finish line.

Rescue workers responded next to a hole in the catch fence.

The No. 31 Brandt Chevrolet, driven by Justin Allgaier, was mangled in the crash.