The chain-reaction pileup on lap 133 involved more than half of the field's cars, but no injuries were reported. AP

TALLADEGA, Ala. (AP) -- A wreck involving 25 cars forced NASCAR officials to temporarily halt the Aaron's 499 Nextel Cup race Sunday at Talladega Superspeedway.

Dale Earnhardt Jr., battling toward the back of the top 10, nudged the rear of Mike Wallace's car on lap 133 as the cars headed toward the first turn on the 133rd of 188 scheduled laps. Wallace then made contact with Jimmie Johnson and slid sideways, setting off a melee that eventually involved more than half of the 43-car field.

So many cars ended up packed together in the muddy infield grass between the first two turns that it looked like an auto junkyard. NASCAR stopped the race to remove the cars and clean up the debris. The stoppage was extended to 43 minutes, 21 seconds to complete repairs to the energy-absorbing barrier at the first turn.

No injuries were reported.

Among the most damaged cars were those of Rusty Wallace, Mark Martin, Ryan Newman, Joe Nemechek, Mike Bliss, Bobby Hamilton Jr., Scott Wimmer, Carl Edwards, Mike Skinner, Kasey Kahne, Brian Vickers and Kyle Busch.

Defending race champion Jeff Gordon was leading, followed by Jamie McMurray, Johnson, Jeff Burton, Earnhardt, Jeremy Mayfield, Martin Truex, Michael Waltrip and Greg Biffle.